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 = 'en' 
WHERE 
  cscart_product_feature_variants.variant_id IN (
    1288, 2108, 1836, 1659, 1202, 1245, 1389, 
    1881, 1251, 1254, 1797, 1690, 1861
  ) 
ORDER BY 
  cscart_product_feature_variants.position ASC, 
  cscart_product_feature_variant_descriptions.variant ASC

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "13.66"
    },
    "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": 13,
            "rows_produced_per_join": 13,
            "filtered": "100.00",
            "index_condition": "(`gaseus`.`cscart_product_feature_variants`.`variant_id` in (1288,2108,1836,1659,1202,1245,1389,1881,1251,1254,1797,1690,1861))",
            "cost_info": {
              "read_cost": "7.81",
              "eval_cost": "1.30",
              "prefix_cost": "9.11",
              "data_read_per_join": "14K"
            },
            "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": [
              "gaseus.cscart_product_feature_variants.variant_id",
              "const"
            ],
            "rows_examined_per_scan": 1,
            "rows_produced_per_join": 13,
            "filtered": "100.00",
            "cost_info": {
              "read_cost": "3.25",
              "eval_cost": "1.30",
              "prefix_cost": "13.66",
              "data_read_per_join": "40K"
            },
            "used_columns": [
              "variant_id",
              "variant",
              "lang_code"
            ]
          }
        }
      ]
    }
  }
}

Result

variant_id position color variant
1288 0 Gastech
1389 0 Linde
1836 0 Stainless steel
1202 0 Vulkan
1659 1 Brass
1254 3 #ffffff Accessories and Spare Parts
1251 3 #ffffff Alarm and Control Systems
1690 3 Brass/Polyamide
1245 3 #ffffff Flexible Hoses
2108 3 Gauges
1881 3 Metall
1861 3 NBR
1797 3 Polyamid