SELECT 
  pfv.variant_id, 
  pfv.position, 
  pfvd.variant 
FROM 
  cscart_product_feature_variants AS pfv 
  INNER JOIN cscart_product_feature_variant_descriptions AS pfvd ON pfv.variant_id = pfvd.variant_id 
  AND pfvd.lang_code = 'ar' 
WHERE 
  pfv.variant_id IN (
    1600, 2315, 1560, 1559, 2985, 2993, 1607, 
    2758, 1609, 1913, 1558, 6255, 1598, 
    1596, 6250, 1556, 6254, 6253, 6252, 
    1914, 6256, 6258, 6257, 6971, 1776, 
    3809, 7191, 2077, 1754, 1681, 1912, 
    6991, 1784, 7064, 7010, 1610, 1599, 
    6360, 3421, 2460, 1755, 7534, 6284, 
    6285, 6290, 6995, 7801, 1595, 5517, 
    1753
  )

Query time 0.00118

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "52.51"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "pfv",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id"
          ],
          "key_length": "3",
          "rows_examined_per_scan": 50,
          "rows_produced_per_join": 50,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`pfv`.`variant_id` in (1600,2315,1560,1559,2985,2993,1607,2758,1609,1913,1558,6255,1598,1596,6250,1556,6254,6253,6252,1914,6256,6258,6257,6971,1776,3809,7191,2077,1754,1681,1912,6991,1784,7064,7010,1610,1599,6360,3421,2460,1755,7534,6284,6285,6290,6995,7801,1595,5517,1753))",
          "cost_info": {
            "read_cost": "30.01",
            "eval_cost": "5.00",
            "prefix_cost": "35.01",
            "data_read_per_join": "57K"
          },
          "used_columns": [
            "variant_id",
            "position"
          ]
        }
      },
      {
        "table": {
          "table_name": "pfvd",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id",
            "lang_code"
          ],
          "key_length": "9",
          "ref": [
            "softwarepirmam_hewadelivard_cscart_4.pfv.variant_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 50,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "12.50",
            "eval_cost": "5.00",
            "prefix_cost": "52.51",
            "data_read_per_join": "151K"
          },
          "used_columns": [
            "variant_id",
            "variant",
            "lang_code"
          ]
        }
      }
    ]
  }
}