SELECT 
  cscart_product_prices.product_id, 
  MIN(
    IF(
      cscart_product_prices.percentage_discount = 0, 
      cscart_product_prices.price, 
      cscart_product_prices.price - (
        cscart_product_prices.price * cscart_product_prices.percentage_discount
      )/ 100
    )
  ) AS price 
FROM 
  cscart_product_prices 
WHERE 
  cscart_product_prices.product_id IN (
    410, 413, 1970, 417, 1937, 414, 425, 407, 
    389, 402, 1972, 388, 426, 409, 1974, 
    404, 1936, 387, 386, 416
  ) 
  AND cscart_product_prices.lower_limit = 1 
  AND cscart_product_prices.usergroup_id IN (0, 1) 
GROUP BY 
  cscart_product_prices.product_id

Query time 0.00099

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "52.21"
    },
    "grouping_operation": {
      "using_filesort": false,
      "table": {
        "table_name": "cscart_product_prices",
        "access_type": "range",
        "possible_keys": [
          "usergroup",
          "product_id",
          "lower_limit",
          "usergroup_id"
        ],
        "key": "product_id",
        "used_key_parts": [
          "product_id"
        ],
        "key_length": "3",
        "rows_examined_per_scan": 23,
        "rows_produced_per_join": 4,
        "filtered": "19.98",
        "index_condition": "(`eshopuga_upgr_4122`.`cscart_product_prices`.`product_id` in (410,413,1970,417,1937,414,425,407,389,402,1972,388,426,409,1974,404,1936,387,386,416))",
        "cost_info": {
          "read_cost": "51.29",
          "eval_cost": "0.92",
          "prefix_cost": "52.21",
          "data_read_per_join": "110"
        },
        "used_columns": [
          "product_id",
          "price",
          "percentage_discount",
          "lower_limit",
          "usergroup_id"
        ],
        "attached_condition": "((`eshopuga_upgr_4122`.`cscart_product_prices`.`lower_limit` = 1) and (`eshopuga_upgr_4122`.`cscart_product_prices`.`usergroup_id` in (0,1)))"
      }
    }
  }
}

Result

product_id price
386 14.000000
387 14.000000
388 14.000000
389 14.000000
402 12.990000
404 14.990000
407 14.990000
409 16.000000
410 14.000000
413 14.990000
414 19.000000
416 15.000000
417 14.000000
425 15.000000
426 14.000000
1936 27.000000
1937 22.000000
1970 23.000000
1972 23.000000
1974 23.000000