SELECT 
  * 
FROM 
  cscart_product_feature_variants 
WHERE 
  variant_id IN (
    1, 178, 182, 334, 197, 335, 399, 410, 190, 
    412, 203, 207, 352, 149, 50, 58, 147, 
    189, 201, 333, 345, 206, 195, 170, 165
  )

Query time 0.00061

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.51"
    },
    "table": {
      "table_name": "cscart_product_feature_variants",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY"
      ],
      "key": "PRIMARY",
      "used_key_parts": [
        "variant_id"
      ],
      "key_length": "3",
      "rows_examined_per_scan": 25,
      "rows_produced_per_join": 25,
      "filtered": "100.00",
      "index_condition": "(`test_uchur_k`.`cscart_product_feature_variants`.`variant_id` in (1,178,182,334,197,335,399,410,190,412,203,207,352,149,50,58,147,189,201,333,345,206,195,170,165))",
      "cost_info": {
        "read_cost": "15.01",
        "eval_cost": "2.50",
        "prefix_cost": "17.51",
        "data_read_per_join": "38K"
      },
      "used_columns": [
        "variant_id",
        "feature_id",
        "url",
        "color",
        "position",
        "abt__ut2_color_style",
        "abt__ut2_multicolor"
      ]
    }
  }
}

Result

variant_id feature_id url color position abt__ut2_color_style abt__ut2_multicolor
1 1 1 default
50 6 0 default
58 6 #ffffff 0 default #ffffff
147 66 #ffffff 0 default #ffffff
149 56 0 default
165 39 #000000 0 default #ffffff
170 39 #999999 0 thumbnail #ffffff
178 1 #ffffff 3 default #ffffff
182 58 0 default
189 39 #d2d293 0 thumbnail #ffffff
190 55 0 default
195 39 #a15723 0 thumbnail #ffffff
197 55 0 default
201 39 #3f0000 0 thumbnail #ffffff
203 55 0 default
206 39 #c2c5cc 0 thumbnail #ffffff
207 55 0 default
333 39 #db65f5 0 thumbnail #ffffff
334 58 0 default
335 55 0 default
345 39 #00ff00 0 thumbnail #ffffff
352 55 0 default
399 55 0 default
410 55 0 default
412 55 0 default