If ATRI -My Dear Moments- generated the same gross revenue on the Epic Games Store, Frontwing, 枕 would keep approximately $9,087,566 - that's $1,944,754 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $1,102,850. Epic charges 0% on the first $1 million in annual per-app revenue and then 12% on the remaining amount. On GOG (30% cut), the developer would earn approximately $7,133,291.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.