SELECT 
  cscart_product_feature_variant_descriptions.variant, 
  cscart_product_feature_variants.variant_id, 
  cscart_product_feature_variants.feature_id, 
  cscart_product_features_values.variant_id as selected, 
  cscart_product_features.feature_type, 
  cscart_seo_names.name as seo_name, 
  cscart_seo_names.path as seo_path, 
  cscart_product_feature_variants.color, 
  cscart_product_features_values.value_int, 
  cscart_product_feature_variant_descriptions.ab__sf_seo_variant 
FROM 
  cscart_product_feature_variants 
  LEFT JOIN cscart_product_feature_variant_descriptions ON cscart_product_feature_variant_descriptions.variant_id = cscart_product_feature_variants.variant_id 
  AND cscart_product_feature_variant_descriptions.lang_code = 'ru' 
  INNER JOIN cscart_product_features_values ON cscart_product_features_values.variant_id = cscart_product_feature_variants.variant_id 
  AND cscart_product_features_values.lang_code = 'ru' 
  AND cscart_product_features_values.product_id = 325 
  AND cscart_product_features_values.feature_id = cscart_product_feature_variants.feature_id 
  LEFT JOIN cscart_product_features ON cscart_product_features.feature_id = cscart_product_feature_variants.feature_id 
  LEFT JOIN cscart_seo_names ON cscart_seo_names.object_id = cscart_product_feature_variants.variant_id 
  AND cscart_seo_names.type = 'e' 
  AND cscart_seo_names.dispatch = '' 
  AND cscart_seo_names.lang_code = 'ru' 
  AND (
    cscart_seo_names.company_id = 1 
    OR cscart_seo_names.company_id = 0
  ) 
WHERE 
  1 
  AND cscart_product_feature_variants.feature_id IN (
    18, 549, 578, 569, 581, 579, 577, 576, 
    580, 573, 571
  ) 
GROUP BY 
  cscart_product_feature_variants.variant_id 
ORDER BY 
  cscart_product_feature_variants.position, 
  cscart_product_feature_variant_descriptions.variant

Query time 0.00187

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.34"
    },
    "ordering_operation": {
      "using_filesort": true,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": false,
        "nested_loop": [
          {
            "table": {
              "table_name": "cscart_product_features_values",
              "access_type": "ref",
              "possible_keys": [
                "PRIMARY",
                "fl",
                "variant_id",
                "lang_code",
                "product_id",
                "fpl",
                "idx_product_feature_variant_id"
              ],
              "key": "product_id",
              "used_key_parts": [
                "product_id"
              ],
              "key_length": "3",
              "ref": [
                "const"
              ],
              "rows_examined_per_scan": 13,
              "rows_produced_per_join": 1,
              "filtered": "8.79",
              "cost_info": {
                "read_cost": "13.00",
                "eval_cost": "0.23",
                "prefix_cost": "15.60",
                "data_read_per_join": "904"
              },
              "used_columns": [
                "feature_id",
                "product_id",
                "variant_id",
                "value_int",
                "lang_code"
              ],
              "attached_condition": "((`44mm_ru`.`cscart_product_features_values`.`feature_id` in (18,549,578,569,581,579,577,576,580,573,571)) and (`44mm_ru`.`cscart_product_features_values`.`lang_code` = 'ru'))"
            }
          },
          {
            "table": {
              "table_name": "cscart_product_feature_variants",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY",
                "feature_id"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "variant_id"
              ],
              "key_length": "3",
              "ref": [
                "44mm_ru.cscart_product_features_values.variant_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "5.00",
              "cost_info": {
                "read_cost": "1.14",
                "eval_cost": "0.01",
                "prefix_cost": "16.97",
                "data_read_per_join": "66"
              },
              "used_columns": [
                "variant_id",
                "feature_id",
                "color",
                "position"
              ],
              "attached_condition": "(`44mm_ru`.`cscart_product_feature_variants`.`feature_id` = `44mm_ru`.`cscart_product_features_values`.`feature_id`)"
            }
          },
          {
            "table": {
              "table_name": "cscart_product_features",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "feature_id"
              ],
              "key_length": "3",
              "ref": [
                "44mm_ru.cscart_product_features_values.feature_id"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.06",
                "eval_cost": "0.01",
                "prefix_cost": "17.04",
                "data_read_per_join": "68"
              },
              "used_columns": [
                "feature_id",
                "feature_type"
              ]
            }
          },
          {
            "table": {
              "table_name": "cscart_product_feature_variant_descriptions",
              "access_type": "eq_ref",
              "possible_keys": [
                "PRIMARY"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "variant_id",
                "lang_code"
              ],
              "key_length": "9",
              "ref": [
                "44mm_ru.cscart_product_features_values.variant_id",
                "const"
              ],
              "rows_examined_per_scan": 1,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.06",
                "eval_cost": "0.01",
                "prefix_cost": "17.11",
                "data_read_per_join": "355"
              },
              "used_columns": [
                "variant_id",
                "variant",
                "lang_code",
                "ab__sf_seo_variant"
              ]
            }
          },
          {
            "table": {
              "table_name": "cscart_seo_names",
              "access_type": "ref",
              "possible_keys": [
                "PRIMARY",
                "dispatch"
              ],
              "key": "PRIMARY",
              "used_key_parts": [
                "object_id",
                "type",
                "dispatch",
                "lang_code"
              ],
              "key_length": "206",
              "ref": [
                "44mm_ru.cscart_product_features_values.variant_id",
                "const",
                "const",
                "const"
              ],
              "rows_examined_per_scan": 3,
              "rows_produced_per_join": 0,
              "filtered": "100.00",
              "cost_info": {
                "read_cost": "0.20",
                "eval_cost": "0.03",
                "prefix_cost": "17.34",
                "data_read_per_join": "297"
              },
              "used_columns": [
                "name",
                "object_id",
                "company_id",
                "type",
                "dispatch",
                "path",
                "lang_code"
              ],
              "attached_condition": "<if>(is_not_null_compl(cscart_seo_names), ((`44mm_ru`.`cscart_seo_names`.`company_id` = 1) or (`44mm_ru`.`cscart_seo_names`.`company_id` = 0)), true)"
            }
          }
        ]
      }
    }
  }
}

Result

variant variant_id feature_id selected feature_type seo_name seo_path color value_int ab__sf_seo_variant
1 7078 581 7078 S
125 7055 576 7055 S
14 7095 569 7095 S
2,5...16 7098 579 7098 S
400 7071 573 7071 S
IEK 89 18 89 E iek
Без изолятора, крепление по краям 7079 578 7079 S
Латунь 7068 577 7068 S
Необработанная 7077 580 7077 S
от -45°C до +80°C 7075 571 7075 S
Китай 1201 549 1201 S