SELECT 
  cscart_product_feature_variants.variant_id, 
  cscart_product_feature_variants.position, 
  cscart_product_feature_variants.color, 
  cscart_product_feature_variant_descriptions.variant 
FROM 
  cscart_product_feature_variants 
  LEFT JOIN cscart_product_feature_variant_descriptions ON cscart_product_feature_variants.variant_id = cscart_product_feature_variant_descriptions.variant_id 
  AND cscart_product_feature_variant_descriptions.lang_code = 'ru' 
WHERE 
  cscart_product_feature_variants.variant_id IN (
    178, 50, 58, 345, 335, 149, 334, 147, 1, 
    170, 333, 352, 195, 190, 189, 182, 201, 
    197, 206, 203, 207, 399, 410, 165, 412
  ) 
ORDER BY 
  cscart_product_feature_variants.position ASC, 
  cscart_product_feature_variant_descriptions.variant ASC

Query time 0.00067

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "26.26"
    },
    "ordering_operation": {
      "using_temporary_table": true,
      "using_filesort": true,
      "nested_loop": [
        {
          "table": {
            "table_name": "cscart_product_feature_variants",
            "access_type": "range",
            "possible_keys": [
              "PRIMARY"
            ],
            "key": "PRIMARY",
            "used_key_parts": [
              "variant_id"
            ],
            "key_length": "3",
            "rows_examined_per_scan": 25,
            "rows_produced_per_join": 25,
            "filtered": "100.00",
            "index_condition": "(`test_uchur_k`.`cscart_product_feature_variants`.`variant_id` in (178,50,58,345,335,149,334,147,1,170,333,352,195,190,189,182,201,197,206,203,207,399,410,165,412))",
            "cost_info": {
              "read_cost": "15.01",
              "eval_cost": "2.50",
              "prefix_cost": "17.51",
              "data_read_per_join": "38K"
            },
            "used_columns": [
              "variant_id",
              "color",
              "position"
            ]
          }
        },
        {
          "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": [
              "test_uchur_k.cscart_product_feature_variants.variant_id",
              "const"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 25,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "6.25",
              "eval_cost": "2.50",
              "prefix_cost": "26.26",
              "data_read_per_join": "77K"
            },
            "used_columns": [
              "variant_id",
              "variant",
              "lang_code"
            ]
          }
        }
      ]
    }
  }
}

Result

variant_id position color variant
197 0 25 MSY3000
335 0 Braid X8
399 0 MS-X
410 0 MS-Y
190 0 MSX3000
412 0 Series for UCHUR
203 0 Series for UCHUR SFU3000
207 0 Series for UCHUR SFU4000
352 0 X8
182 0 Алюминий
50 0 Демисезон
189 0 #d2d293 Желтый/Серый
147 0 #ffffff Китай
201 0 #3f0000 Красный/Черный
58 0 #ffffff Лето
334 0 Полиэтилен
333 0 #db65f5 Разноцветный
149 0 Рыбалка
345 0 #00ff00 Светло-зеленый
206 0 #c2c5cc Серебристый
195 0 #a15723 Серо-оранжевый
170 0 #999999 Серый
165 0 #000000 Черный
1 1 UCHUR
178 3 #ffffff МУНХА