SELECT 
  pfv.feature_id, 
  pfv.product_id, 
  pfv.variant_id, 
  fv.position, 
  fvd.variant 
FROM 
  cscart_product_features_values AS pfv 
  INNER JOIN cscart_product_feature_variants AS fv ON pfv.feature_id = fv.feature_id 
  AND pfv.variant_id = fv.variant_id 
  INNER JOIN cscart_product_feature_variant_descriptions AS fvd ON pfv.variant_id = fvd.variant_id 
  AND fvd.lang_code = 'ru' 
WHERE 
  pfv.feature_id IN (193, 3) 
  AND pfv.product_id IN (
    51567, 
    51565, 
    51564, 
    139, 
    129, 
    51566, 
    51301, 
    51, 
    50, 
    51497, 
    51498, 
    53, 
    22713, 
    21, 
    22714, 
    22712, 
    46, 
    22715, 
    22716, 
    51496, 
    21567, 
    91, 
    50989, 
    47, 
    105, 
    48, 
    49, 
    92, 
    137, 
    88, 
    126, 
    31, 
    51358, 
    115, 
    37, 
    11, 
    140, 
    41, 
    30, 
    90, 
    38, 
    124, 
    81, 
    56, 
    135, 
    82, 
    116, 
    117, 
    125, 
    106, 
    39, 
    65, 
    40, 
    22710, 
    22711, 
    17, 
    57, 
    122, 
    58, 
    5, 
    22, 
    18, 
    27, 
    121, 
    119, 
    141, 
    23, 
    4, 
    142, 
    120, 
    62, 
    108, 
    107, 
    94, 
    8, 
    86, 
    54, 
    10, 
    93, 
    12, 
    32, 
    7, 
    130, 
    35, 
    16, 
    33, 
    110, 
    34, 
    89, 
    147, 
    114, 
    36, 
    128, 
    20, 
    52, 
    84, 
    109, 
    118, 
    19, 
    131, 
    146, 
    13, 
    61, 
    95, 
    15, 
    9, 
    85, 
    59, 
    111, 
    144, 
    60, 
    123, 
    145, 
    113, 
    6, 
    14, 
    63, 
    136, 
    50984, 
    127, 
    134, 
    42, 
    50985, 
    50986, 
    50988, 
    50993, 
    50992
  ) 
  AND pfv.lang_code = 'ru'

Query time 0.00364

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "102.30"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "pfv",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "variant_id",
            "lang_code",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "feature_id",
            "product_id"
          ],
          "key_length": "6",
          "rows_examined_per_scan": 254,
          "rows_produced_per_join": 130,
          "filtered": "51.30",
          "using_index": true,
          "cost_info": {
            "read_cost": "40.56",
            "eval_cost": "13.03",
            "prefix_cost": "53.59",
            "data_read_per_join": "100K"
          },
          "used_columns": [
            "feature_id",
            "product_id",
            "variant_id",
            "lang_code"
          ],
          "attached_condition": "((`test_uchur_k`.`pfv`.`feature_id` in (193,3)) and (`test_uchur_k`.`pfv`.`product_id` in (51567,51565,51564,139,129,51566,51301,51,50,51497,51498,53,22713,21,22714,22712,46,22715,22716,51496,21567,91,50989,47,105,48,49,92,137,88,126,31,51358,115,37,11,140,41,30,90,38,124,81,56,135,82,116,117,125,106,39,65,40,22710,22711,17,57,122,58,5,22,18,27,121,119,141,23,4,142,120,62,108,107,94,8,86,54,10,93,12,32,7,130,35,16,33,110,34,89,147,114,36,128,20,52,84,109,118,19,131,146,13,61,95,15,9,85,59,111,144,60,123,145,113,6,14,63,136,50984,127,134,42,50985,50986,50988,50993,50992)) and (`test_uchur_k`.`pfv`.`lang_code` = 'ru'))"
        }
      },
      {
        "table": {
          "table_name": "fv",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY",
            "feature_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id"
          ],
          "key_length": "3",
          "ref": [
            "test_uchur_k.pfv.variant_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 8,
          "filtered": "6.81",
          "cost_info": {
            "read_cost": "32.57",
            "eval_cost": "0.89",
            "prefix_cost": "99.19",
            "data_read_per_join": "13K"
          },
          "used_columns": [
            "variant_id",
            "feature_id",
            "position"
          ],
          "attached_condition": "(`test_uchur_k`.`fv`.`feature_id` = `test_uchur_k`.`pfv`.`feature_id`)"
        }
      },
      {
        "table": {
          "table_name": "fvd",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id",
            "lang_code"
          ],
          "key_length": "9",
          "ref": [
            "test_uchur_k.pfv.variant_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 8,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "2.22",
            "eval_cost": "0.89",
            "prefix_cost": "102.30",
            "data_read_per_join": "27K"
          },
          "used_columns": [
            "variant_id",
            "variant",
            "lang_code"
          ]
        }
      }
    ]
  }
}