As always, it depends. Building something like Unity/Unreal that should support everything and everyone under the sun, one way or another? Yeah, huge time sink.

As always, it depends. Building something like Unity/Unreal that should support everything and everyone under the sun, one way or another? Yeah, huge time sink. But a 2D engine that should only support exactly what the features need from Stardew Valley? Doesn't seem insurmountable, although I wouldn't exactly take that approach myself.