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 = 'vi' 
WHERE 
  pfv.variant_id IN (
    82511, 82514, 82515, 82512, 82513, 82571, 
    82573, 82574, 82572, 82576, 82575, 
    82568, 82566, 82565, 82570, 82567, 
    82569, 82563, 82564, 82583, 82582, 
    82584, 82585, 82581, 82580, 82579, 
    82578, 82590, 82577, 82586, 82587, 
    82589, 82588, 82591, 82599, 82596, 
    82597, 82598, 82593, 82594, 82595, 
    82600, 82601, 82592, 82636, 82652, 
    82645, 82653, 82654, 82655, 82656, 
    82646, 82649, 82650, 82651, 82647, 
    82637, 82638, 82639, 82640, 82641, 
    82642, 82643, 82644, 85875, 85874, 
    85873, 85872, 85876, 85877, 85878, 
    85879, 85880, 85881, 85882, 85864, 
    85865, 85866, 85867, 85868, 85869, 
    85870, 85871
  )

Query time 0.00724

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": 83,
          "filtered": 100,
          "index_condition": "pfv.variant_id in (82511,82514,82515,82512,82513,82571,82573,82574,82572,82576,82575,82568,82566,82565,82570,82567,82569,82563,82564,82583,82582,82584,82585,82581,82580,82579,82578,82590,82577,82586,82587,82589,82588,82591,82599,82596,82597,82598,82593,82594,82595,82600,82601,82592,82636,82652,82645,82653,82654,82655,82656,82646,82649,82650,82651,82647,82637,82638,82639,82640,82641,82642,82643,82644,85875,85874,85873,85872,85876,85877,85878,85879,85880,85881,85882,85864,85865,85866,85867,85868,85869,85870,85871)"
        }
      },
      {
        "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 = 'vi'"
        }
      }
    ]
  }
}