SELECT 
  v.variant_id, 
  v.product_id, 
  vd.variant, 
  vf.position, 
  vf.color 
FROM 
  cscart_product_features_values v 
  LEFT JOIN cscart_product_feature_variant_descriptions vd ON v.variant_id = vd.variant_id 
  AND vd.lang_code = 'en' 
  LEFT JOIN cscart_product_feature_variants vf ON v.variant_id = vf.variant_id 
WHERE 
  1 
  AND v.feature_id = 1446 
  AND v.product_id IN (
    '62270', '62271', '62272', '62273', 
    '62274', '62275', '62276', '62277', 
    '62278', '62279', '62280', '62281', 
    '62282', '62283', '62284', '62285', 
    '62286', '62287', '62288', '62289', 
    '62290', '62291', '62292', '62293'
  )

Query time 0.00135

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "23.00"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "v",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "idx_product_feature_variant_id",
          "used_key_parts": [
            "product_id",
            "feature_id"
          ],
          "key_length": "6",
          "rows_examined_per_scan": 25,
          "rows_produced_per_join": 25,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "3.00",
            "eval_cost": "2.50",
            "prefix_cost": "5.50",
            "data_read_per_join": "19K"
          },
          "used_columns": [
            "feature_id",
            "product_id",
            "variant_id"
          ],
          "attached_condition": "((`cscartdb`.`v`.`feature_id` = 1446) and (`cscartdb`.`v`.`product_id` in ('62270','62271','62272','62273','62274','62275','62276','62277','62278','62279','62280','62281','62282','62283','62284','62285','62286','62287','62288','62289','62290','62291','62292','62293')))"
        }
      },
      {
        "table": {
          "table_name": "vd",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id",
            "lang_code"
          ],
          "key_length": "9",
          "ref": [
            "cscartdb.v.variant_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 25,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "6.25",
            "eval_cost": "2.50",
            "prefix_cost": "14.25",
            "data_read_per_join": "75K"
          },
          "used_columns": [
            "variant_id",
            "variant",
            "lang_code"
          ]
        }
      },
      {
        "table": {
          "table_name": "vf",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "variant_id"
          ],
          "key_length": "3",
          "ref": [
            "cscartdb.v.variant_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 25,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "6.25",
            "eval_cost": "2.50",
            "prefix_cost": "23.00",
            "data_read_per_join": "28K"
          },
          "used_columns": [
            "variant_id",
            "color",
            "position"
          ]
        }
      }
    ]
  }
}

Result

variant_id product_id variant position color
5822 62270 Soft 0 #000000
5823 62271 Medium 1 #000000
5824 62272 Firm 2 #000000
5822 62273 Soft 0 #000000
5823 62274 Medium 1 #000000
5824 62275 Firm 2 #000000
5822 62276 Soft 0 #000000
5823 62277 Medium 1 #000000
5824 62278 Firm 2 #000000
5822 62279 Soft 0 #000000
5823 62280 Medium 1 #000000
5824 62281 Firm 2 #000000
5822 62282 Soft 0 #000000
5823 62283 Medium 1 #000000
5824 62284 Firm 2 #000000
5822 62285 Soft 0 #000000
5823 62286 Medium 1 #000000
5824 62287 Firm 2 #000000
5822 62288 Soft 0 #000000
5823 62289 Medium 1 #000000
5824 62290 Firm 2 #000000
5822 62291 Soft 0 #000000
5823 62292 Medium 1 #000000
5824 62293 Firm 2 #000000