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 (
    1686, 1633, 1612, 1632, 1631, 1611, 1614, 
    1687, 1553, 1637, 1636, 1635, 1634, 
    1613, 1615, 1554, 1726, 1725, 1724, 
    1792, 1607, 1560, 1793, 2231, 2237, 
    1597, 2243, 1599, 2423, 2758, 1609, 
    1559, 2077, 1596, 1600, 1674, 1555, 
    1790, 8611, 8612, 5563, 1558, 9493, 
    9224, 9225
  )

Query time 0.00129

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "47.26"
    },
    "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": 45,
          "rows_produced_per_join": 45,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`pfv`.`variant_id` in (1686,1633,1612,1632,1631,1611,1614,1687,1553,1637,1636,1635,1634,1613,1615,1554,1726,1725,1724,1792,1607,1560,1793,2231,2237,1597,2243,1599,2423,2758,1609,1559,2077,1596,1600,1674,1555,1790,8611,8612,5563,1558,9493,9224,9225))",
          "cost_info": {
            "read_cost": "27.01",
            "eval_cost": "4.50",
            "prefix_cost": "31.51",
            "data_read_per_join": "51K"
          },
          "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": 45,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "11.25",
            "eval_cost": "4.50",
            "prefix_cost": "47.26",
            "data_read_per_join": "136K"
          },
          "used_columns": [
            "variant_id",
            "variant",
            "lang_code"
          ]
        }
      }
    ]
  }
}