If Overcooked! 2 generated the same gross revenue on the Epic Games Store, Ghost Town Games Ltd. would keep approximately $26,527,544 - that's $4,521,114 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $3,481,029. 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 $21,006,001.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.