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 = 'en' 
WHERE 
  pfv.variant_id IN (
    74226, 74227, 74613, 74612, 74611, 74614, 
    74936, 74935, 74934, 74937, 74964, 
    74963, 74962, 74961, 74965, 79224, 
    79225, 79223, 79643, 80590, 80591, 
    80592, 80722, 80723, 80724, 81002, 
    81003, 81004, 81005, 81006, 81007, 
    85957, 85956, 85955, 85954, 85959, 
    85958, 82399, 82400, 82401, 84207, 
    84208, 84405, 84406, 84407, 84408, 
    87126, 87127, 87128, 87129
  )

Query time 0.00378

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "pfv",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["variant_id"],
          "rows": 50,
          "filtered": 100,
          "index_condition": "pfv.variant_id in (74226,74227,74613,74612,74611,74614,74936,74935,74934,74937,74964,74963,74962,74961,74965,79224,79225,79223,79643,80590,80591,80592,80722,80723,80724,81002,81003,81004,81005,81006,81007,85957,85956,85955,85954,85959,85958,82399,82400,82401,84207,84208,84405,84406,84407,84408,87126,87127,87128,87129)"
        }
      },
      {
        "table": {
          "table_name": "pfvd",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "9",
          "used_key_parts": ["variant_id", "lang_code"],
          "ref": ["dev_db.pfv.variant_id", "const"],
          "rows": 1,
          "filtered": 100,
          "index_condition": "pfvd.lang_code = 'en'"
        }
      }
    ]
  }
}