SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  descr1.product as product, 
  companies.company as company_name, 
  products.product_type, 
  products.parent_product_id, 
  products.master_product_offers_count, 
  products.master_product_id, 
  products.company_id 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'fr' 
  LEFT JOIN cscart_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  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_master_products_storefront_offers_count AS master_products_storefront_offers_count ON master_products_storefront_offers_count.product_id = products.product_id 
  AND master_products_storefront_offers_count.storefront_id = 1 
WHERE 
  1 
  AND (
    companies.status IN ('A') 
    OR products.company_id = 0
  ) 
  AND (
    products.amount > 0 
    OR products.tracking = 'D' 
    OR products.tracking IS NULL
  ) 
  AND products.product_id IN (
    662, 666, 663, 348, 661, 350, 719, 313, 
    665, 659, 629, 307, 398
  ) 
  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 prices.usergroup_id IN (0, 0, 1) 
  AND products.master_product_status IN ('A', 'H') 
  AND products.master_product_id = 0 
  AND (
    products.company_id > 0 
    OR (
      master_products_storefront_offers_count.count > 0
    )
  ) 
GROUP BY 
  products.product_id 
ORDER BY 
  products_categories.position asc, 
  products.product_id ASC

Query time 0.00072

JSON explain

{
  "query_block": {
    "select_id": 1,
    "filesort": {
      "sort_key": "products_categories.position, products.product_id",
      "temporary_table": {
        "table": {
          "table_name": "master_products_storefront_offers_count",
          "access_type": "system",
          "possible_keys": ["PRIMARY", "idx_storefront_id"],
          "rows": 0,
          "filtered": 0,
          "const_row_not_found": true
        },
        "table": {
          "table_name": "products",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "status", "idx_master_product_id"],
          "key": "status",
          "key_length": "6",
          "used_key_parts": ["status", "product_id"],
          "rowid_filter": {
            "range": {
              "key": "idx_master_product_id",
              "used_key_parts": ["master_product_id", "product_id"]
            },
            "rows": 13,
            "selectivity_pct": 12.74509804
          },
          "rows": 13,
          "filtered": 100,
          "index_condition": "products.product_id in (662,666,663,348,661,350,719,313,665,659,629,307,398) and products.`status` = 'A'",
          "attached_condition": "products.master_product_id = 0 and (products.amount > 0 or products.tracking = 'D' or products.tracking is null) and (products.usergroup_ids = '' or find_in_set(0,products.usergroup_ids) or find_in_set(1,products.usergroup_ids)) and products.master_product_status in ('A','H') and products.company_id > 0"
        },
        "table": {
          "table_name": "companies",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "4",
          "used_key_parts": ["company_id"],
          "ref": ["multi_vendor.products.company_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "trigcond(companies.`status` = 'A' or products.company_id = 0)"
        },
        "table": {
          "table_name": "products_categories",
          "access_type": "ref",
          "possible_keys": ["PRIMARY", "pt"],
          "key": "pt",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "ref": ["multi_vendor.products.product_id"],
          "rows": 1,
          "filtered": 100
        },
        "table": {
          "table_name": "cscart_categories",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "c_status", "p_category_id"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["category_id"],
          "ref": ["multi_vendor.products_categories.category_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "(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)"
        },
        "table": {
          "table_name": "prices",
          "access_type": "ref",
          "possible_keys": [
            "usergroup",
            "product_id",
            "lower_limit",
            "usergroup_id"
          ],
          "key": "product_id",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "ref": ["multi_vendor.products.product_id"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "prices.lower_limit = 1 and prices.usergroup_id in (0,0,1)",
          "using_index": true
        },
        "table": {
          "table_name": "descr1",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY", "product_id"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["product_id", "lang_code"],
          "ref": ["multi_vendor.products.product_id", "const"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "trigcond(descr1.lang_code = 'fr')"
        }
      }
    }
  }
}