SELECT 
  SQL_CALC_FOUND_ROWS products.product_id, 
  descr1.product as product, 
  companies.company as company_name, 
  products.product_type, 
  products.parent_product_id, 
  ec.energy_class as energy_class, 
  ec.label_path as energy_label_path, 
  ec.datasheet_value as energy_datasheet_value 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'ru' 
  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_energy_compliance as ec ON ec.product_id = products.product_id 
WHERE 
  1 
  AND products.product_id NOT IN (281) 
  AND companies.status IN ('A') 
  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 (
    (
      1 
      AND products.product_id IN (280)
    ) 
    AND companies.status IN ('A') 
    AND prices.usergroup_id IN (0, 0, 1)
  ) 
GROUP BY 
  products.product_id 
ORDER BY 
  product asc, 
  products.product_id ASC 
LIMIT 
  0, 6

Query time 0.01718

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "products",
          "access_type": "const",
          "possible_keys": ["PRIMARY", "status"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "ref": ["const"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "descr1",
          "access_type": "const",
          "possible_keys": ["PRIMARY", "product_id"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["product_id", "lang_code"],
          "ref": ["const", "const"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "companies",
          "access_type": "const",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "4",
          "used_key_parts": ["company_id"],
          "ref": ["const"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "ec",
          "access_type": "system",
          "possible_keys": ["PRIMARY"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "products_categories",
          "access_type": "ref",
          "possible_keys": ["PRIMARY", "pt"],
          "key": "pt",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "ref": ["const"],
          "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": ["cscart.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)"
        }
      },
      {
        "block-nl-join": {
          "table": {
            "table_name": "prices",
            "access_type": "range",
            "possible_keys": [
              "usergroup",
              "product_id",
              "lower_limit",
              "usergroup_id"
            ],
            "key": "usergroup",
            "key_length": "9",
            "used_key_parts": ["product_id", "usergroup_id", "lower_limit"],
            "rows": 2,
            "filtered": 100,
            "attached_condition": "prices.product_id = 280 and prices.lower_limit = 1 and prices.usergroup_id in (0,0,1) and prices.usergroup_id in (0,0,1)",
            "using_index": true
          },
          "buffer_type": "flat",
          "buffer_size": "8Kb",
          "join_type": "BNL"
        }
      }
    ]
  }
}

Result

product_id product company_name product_type parent_product_id energy_class energy_label_path energy_datasheet_value
280 Футболка, Цвет: Черный CS-Cart P 0