SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  descr1.product as product, 
  companies.company as company_name, 
  MIN(
    IF(
      prices.percentage_discount = 0, 
      prices.price, 
      prices.price - (
        prices.price * prices.percentage_discount
      )/ 100
    )
  ) as price, 
  products.product_type, 
  products.parent_product_id, 
  products.master_product_offers_count, 
  products.master_product_id, 
  products.company_id 
FROM 
  tmall_products as products 
  LEFT JOIN tmall_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'en' 
  LEFT JOIN tmall_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  LEFT JOIN tmall_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN tmall_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN tmall_categories ON tmall_categories.category_id = products_categories.category_id 
  AND (
    tmall_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, tmall_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, tmall_categories.usergroup_ids
    )
  ) 
  AND tmall_categories.status IN ('A', 'H') 
  AND tmall_categories.storefront_id IN (0, 1) 
WHERE 
  1 
  AND (
    companies.status IN ('A') 
    OR products.company_id = 0
  ) 
  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 = 242 
GROUP BY 
  products.product_id 
ORDER BY 
  price asc, 
  products.product_id ASC

Query time 0.00828

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.085043638,
    "filesort": {
      "sort_key": "min(if(prices.percentage_discount = 0,prices.price,prices.price - prices.price * prices.percentage_discount / 100)), products.product_id",
      "temporary_table": {
        "nested_loop": [
          {
            "table": {
              "table_name": "products",
              "access_type": "ref",
              "possible_keys": ["PRIMARY", "status", "idx_master_product_id"],
              "key": "idx_master_product_id",
              "key_length": "4",
              "used_key_parts": ["master_product_id"],
              "ref": ["const"],
              "loops": 1,
              "rows": 1,
              "cost": 0.002024411,
              "filtered": 93.65079498,
              "attached_condition": "products.master_product_id <=> 242 and (products.usergroup_ids = '' or find_in_set(0,products.usergroup_ids) or find_in_set(1,products.usergroup_ids)) and products.`status` = 'A' and products.master_product_status in ('A','H')"
            }
          },
          {
            "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": ["tmall.products.product_id", "const"],
              "loops": 1,
              "rows": 1,
              "cost": 0.001933826,
              "filtered": 100,
              "attached_condition": "trigcond(descr1.lang_code = 'en')"
            }
          },
          {
            "table": {
              "table_name": "companies",
              "access_type": "eq_ref",
              "possible_keys": ["PRIMARY"],
              "key": "PRIMARY",
              "key_length": "4",
              "used_key_parts": ["company_id"],
              "ref": ["tmall.products.company_id"],
              "loops": 1,
              "rows": 1,
              "cost": 0.001933826,
              "filtered": 100,
              "attached_condition": "trigcond(companies.`status` = 'A' or products.company_id = 0)"
            }
          },
          {
            "table": {
              "table_name": "prices",
              "access_type": "ref",
              "possible_keys": [
                "usergroup",
                "product_id",
                "lower_limit",
                "usergroup_id"
              ],
              "key": "usergroup",
              "key_length": "3",
              "used_key_parts": ["product_id"],
              "ref": ["tmall.products.product_id"],
              "loops": 1,
              "rows": 2,
              "cost": 0.00327684,
              "filtered": 93.5160141,
              "index_condition": "prices.lower_limit = 1 and prices.usergroup_id in (0,0,1)"
            }
          },
          {
            "table": {
              "table_name": "products_categories",
              "access_type": "ref",
              "possible_keys": ["PRIMARY", "pt"],
              "key": "pt",
              "key_length": "3",
              "used_key_parts": ["product_id"],
              "ref": ["tmall.products.product_id"],
              "loops": 2.25952504,
              "rows": 11,
              "cost": 0.032405992,
              "filtered": 100
            }
          },
          {
            "table": {
              "table_name": "tmall_categories",
              "access_type": "eq_ref",
              "possible_keys": ["PRIMARY", "c_status", "p_category_id"],
              "key": "PRIMARY",
              "key_length": "3",
              "used_key_parts": ["category_id"],
              "ref": ["tmall.products_categories.category_id"],
              "loops": 25.02214767,
              "rows": 1,
              "cost": 0.043468744,
              "filtered": 100,
              "attached_condition": "(tmall_categories.usergroup_ids = '' or find_in_set(0,tmall_categories.usergroup_ids) or find_in_set(1,tmall_categories.usergroup_ids)) and tmall_categories.`status` in ('A','H') and tmall_categories.storefront_id in (0,1)"
            }
          }
        ]
      }
    }
  }
}