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, 2993, 1913, 1558, 
    6250, 2077, 1599, 6252, 6253, 6257, 
    6258, 6360, 7010, 1610, 1598, 1556, 
    1596, 7534, 6284, 6285, 6290, 6995, 
    7064, 5517, 1753, 6255, 6256
  )

Query time 0.00113

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "31.51"
    },
    "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": 30,
          "rows_produced_per_join": 30,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`pfv`.`variant_id` in (1600,2315,1560,1559,2993,1913,1558,6250,2077,1599,6252,6253,6257,6258,6360,7010,1610,1598,1556,1596,7534,6284,6285,6290,6995,7064,5517,1753,6255,6256))",
          "cost_info": {
            "read_cost": "18.01",
            "eval_cost": "3.00",
            "prefix_cost": "21.01",
            "data_read_per_join": "34K"
          },
          "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": 30,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "7.50",
            "eval_cost": "3.00",
            "prefix_cost": "31.51",
            "data_read_per_join": "90K"
          },
          "used_columns": [
            "variant_id",
            "variant",
            "lang_code"
          ]
        }
      }
    ]
  }
}