If HighFleet generated the same gross revenue on the Epic Games Store, Konstantin Koshutin would keep approximately $4,643,901 - that's $1,045,343 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $496,896. 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 $3,598,557.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.