If SD GUNDAM G GENERATION CROSS RAYS generated the same gross revenue on the Epic Games Store, TOM CREATE would keep approximately $4,775,168 - that's $1,072,193 more than on Steam.
At this revenue level, Epic's concrete platform fee would be $514,796. 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 $3,702,975.
Note: This is a hypothetical comparison. Actual sales volumes differ significantly between platforms, and Steam's larger user base typically drives substantially higher sales.