SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  products.amount, 
  descr1.product as product, 
  companies.company as company_name, 
  variation_group_products.group_id AS variation_group_id, 
  products.product_type, 
  products.parent_product_id 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'en' 
  LEFT JOIN cscart_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN cscart_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN cscart_categories ON cscart_categories.category_id = products_categories.category_id 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  AND cscart_categories.storefront_id IN (0, 1) 
  LEFT JOIN cscart_warehouses_sum_products_amount as war_sum_amount ON war_sum_amount.product_id = products.product_id 
  LEFT JOIN cscart_warehouses_destination_products_amount AS warehouses_destination_products_amount ON warehouses_destination_products_amount.product_id = products.product_id 
  AND warehouses_destination_products_amount.destination_id = 0 
  AND warehouses_destination_products_amount.storefront_id = 0 
  INNER JOIN cscart_product_variation_group_products AS variation_group_products ON variation_group_products.product_id = products.product_id 
WHERE 
  1 
  AND companies.status IN ('A') 
  AND products.company_id IN (
    26, 80, 85, 86, 87, 88, 89, 90, 91, 101, 
    102, 103, 104, 0
  ) 
  AND (
    (
      CASE products.is_stock_split_by_warehouses WHEN 'Y' THEN warehouses_destination_products_amount.amount ELSE products.amount END
    ) > 0 
    OR products.tracking = 'D'
  ) 
  AND (
    products.usergroup_ids = '' 
    OR FIND_IN_SET(0, products.usergroup_ids) 
    OR FIND_IN_SET(1, products.usergroup_ids)
  ) 
  AND products.status IN ('A') 
  AND variation_group_products.group_id IN (462, 459) 
GROUP BY 
  products.product_id 
ORDER BY 
  NULL asc

Query time 0.00148

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "11.61"
    },
    "ordering_operation": {
      "using_filesort": false,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": false,
        "nested_loop": [
          {
            "table": {
              "table_name": "cscart_categories",
              "access_type": "ALL",
              "possible_keys": [
                "PRIMARY",
                "c_status",
                "p_category_id"
              ],
              "rows_examined_per_scan": 15,
              "rows_produced_per_join": 0,
              "filtered": "6.67",
              "cost_info": {
                "read_cost": "1.65",
                "eval_cost": "0.10",
                "prefix_cost": "1.75",
                "data_read_per_join": "2K"
              },
              "used_columns": [
                "category_id",
                "usergroup_ids",
                "status",
                "storefront_id"
              ],
              "attached_condition": "(((`shoptheindependents_com`.`cscart_categories`.`usergroup_ids` = '') or (0 <> find_in_set(0,`shoptheindependents_com`.`cscart_categories`.`usergroup_ids`)) or (0 <> find_in_set(1,`shoptheindependents_com`.`cscart_categories`.`usergroup_ids`))) and (`shoptheindependents_com`.`cscart_categories`.`status` in ('A','H')) and (`shoptheindependents_com`.`cscart_categories`.`storefront_id` in (0,1)))"
            }
          },
          {
            "table": {
              "table_name": "companies",
              "access_type": "ALL",
              "possible_keys": [
                "PRIMARY"
              ],
              "rows_examined_per_scan": 13,
              "rows_produced_per_join": 1,
              "filtered": "10.00",
              "using_join_buffer": "hash join",
              "cost_info": {
                "read_cost": "1.42",
                "eval_cost": "0.13",
                "prefix_cost": "3.30",
                "data_read_per_join": "14K"
              },
              "used_columns": [
                "company_id",
                "status",
                "company"
              ],
              "attached_condition": "((`shoptheindependents_com`.`companies`.`status` = 'A') and (`shoptheindependents_com`.`companies`.`company_id` in (26,80,85,86,87,88,89,90,91,101,102,103,104,0)))"
            }
          },
          {
            "table": {
              "table_name": "products_categories",
              "access_type": "ref",
              "possible_keys": [
                "PRIMARY",
                "pt"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "category_id"
              ],
              "key_length": "3",
              "ref": [
                "shoptheindependents_com.cscart_categories.category_id"
              ],
              "rows_examined_per_scan": 13,
              "rows_produced_per_join": 18,
              "filtered": "100.00",
              "using_index": true,
              "cost_info": {
                "read_cost": "0.33",
                "eval_cost": "1.81",
                "prefix_cost": "5.44",
                "data_read_per_join": "289"
              },
              "used_columns": [
                "product_id",
                "category_id"
              ]
            }
          },
          {
            "table": {
              "table_name": "products",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "age_verification",
                "status",
                "idx_parent_product_id",
                "idx_master_product_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "shoptheindependents_com.products_categories.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "5.00",
              "cost_info": {
                "read_cost": "3.47",
                "eval_cost": "0.09",
                "prefix_cost": "10.72",
                "data_read_per_join": "4K"
              },
              "used_columns": [
                "product_id",
                "product_type",
                "status",
                "company_id",
                "amount",
                "usergroup_ids",
                "tracking",
                "parent_product_id",
                "is_stock_split_by_warehouses"
              ],
              "attached_condition": "((`shoptheindependents_com`.`products`.`company_id` = `shoptheindependents_com`.`companies`.`company_id`) and ((`shoptheindependents_com`.`products`.`usergroup_ids` = '') or (0 <> find_in_set(0,`shoptheindependents_com`.`products`.`usergroup_ids`)) or (0 <> find_in_set(1,`shoptheindependents_com`.`products`.`usergroup_ids`))) and (`shoptheindependents_com`.`products`.`status` = 'A'))"
            }
          },
          {
            "table": {
              "table_name": "variation_group_products",
              "access_type": "ref",
              "possible_keys": [
                "PRIMARY",
                "idx_group_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "shoptheindependents_com.products_categories.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "57.78",
              "using_index": true,
              "cost_info": {
                "read_cost": "0.23",
                "eval_cost": "0.06",
                "prefix_cost": "11.05",
                "data_read_per_join": "9"
              },
              "used_columns": [
                "product_id",
                "group_id"
              ],
              "attached_condition": "(`shoptheindependents_com`.`variation_group_products`.`group_id` in (462,459))"
            }
          },
          {
            "table": {
              "table_name": "war_sum_amount",
              "access_type": "ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "shoptheindependents_com.products_categories.product_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "using_index": true,
              "cost_info": {
                "read_cost": "0.15",
                "eval_cost": "0.06",
                "prefix_cost": "11.26",
                "data_read_per_join": "9"
              },
              "used_columns": [
                "storefront_id",
                "product_id"
              ]
            }
          },
          {
            "table": {
              "table_name": "warehouses_destination_products_amount",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "idx_storefront_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id",
                "destination_id",
                "storefront_id"
              ],
              "key_length": "9",
              "ref": [
                "shoptheindependents_com.products_categories.product_id",
                "const",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.12",
                "eval_cost": "0.06",
                "prefix_cost": "11.44",
                "data_read_per_join": "9"
              },
              "used_columns": [
                "destination_id",
                "storefront_id",
                "product_id",
                "amount"
              ],
              "attached_condition": "<if>(found_match(warehouses_destination_products_amount), (((case `shoptheindependents_com`.`products`.`is_stock_split_by_warehouses` when 'Y' then `shoptheindependents_com`.`warehouses_destination_products_amount`.`amount` else `shoptheindependents_com`.`products`.`amount` end) > 0) or (`shoptheindependents_com`.`products`.`tracking` = 'D')), true)"
            }
          },
          {
            "table": {
              "table_name": "descr1",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "product_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "product_id",
                "lang_code"
              ],
              "key_length": "9",
              "ref": [
                "shoptheindependents_com.products_categories.product_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.12",
                "eval_cost": "0.06",
                "prefix_cost": "11.61",
                "data_read_per_join": "2K"
              },
              "used_columns": [
                "product_id",
                "lang_code",
                "product"
              ]
            }
          }
        ]
      }
    }
  }
}

Result

product_id amount product company_name variation_group_id product_type parent_product_id
3077 2 Louise Slide Sandal Sophia's Shop 462 P 0
3078 9 Louise Slide Sandal Sophia's Shop 462 V 3077
3017 6 Asher Jacket Sophia's Shop 459 V 3022
3018 6 Asher Jacket Sophia's Shop 459 V 3022
3019 1 Asher Jacket Sophia's Shop 459 V 3022
3020 2 Asher Jacket Sophia's Shop 459 V 3022
3021 6 Asher Jacket Sophia's Shop 459 V 3022
3022 5 Asher Jacket Sophia's Shop 459 P 0
3074 5 Louise Slide Sandal Sophia's Shop 462 V 3073
3075 7 Louise Slide Sandal Sophia's Shop 462 P 0
3076 9 Louise Slide Sandal Sophia's Shop 462 V 3075