SELECT 
  cscart_product_review_prepared_data.product_id AS product_id, 
  cscart_product_review_prepared_data.average_rating AS average_rating, 
  cscart_product_review_prepared_data.reviews_count AS reviews_count 
FROM 
  cscart_product_review_prepared_data 
WHERE 
  cscart_product_review_prepared_data.product_id IN (
    264699, 339789, 339784, 339788, 339785, 
    339790, 339800, 339793, 339792, 339801, 
    339799, 339791, 339795, 339803, 339786, 
    339796, 339797, 339798, 339794, 339805
  ) 
  AND cscart_product_review_prepared_data.storefront_id = 0

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "5.87"
    },
    "table": {
      "table_name": "cscart_product_review_prepared_data",
      "access_type": "ALL",
      "possible_keys": [
        "PRIMARY"
      ],
      "rows_examined_per_scan": 19,
      "rows_produced_per_join": 19,
      "filtered": "100.00",
      "cost_info": {
        "read_cost": "2.07",
        "eval_cost": "3.80",
        "prefix_cost": "5.87",
        "data_read_per_join": "304"
      },
      "used_columns": [
        "product_id",
        "storefront_id",
        "average_rating",
        "reviews_count"
      ],
      "attached_condition": "((`webmarco`.`cscart_product_review_prepared_data`.`storefront_id` = 0) and (`webmarco`.`cscart_product_review_prepared_data`.`product_id` in (264699,339789,339784,339788,339785,339790,339800,339793,339792,339801,339799,339791,339795,339803,339786,339796,339797,339798,339794,339805)))"
    }
  }
}