So I tried to play it something like splitscreen with keyboard+x360controller, but there was one thing that break all fun.
When I moving mouse anywhere, xbcm interface is dissapearing in window with terraria with xbcm. Cause of this I can't play it with my brother on same PC. So when mouse is idle, everything fine. Both player in both windows can move, jump etc. But when mouse is moving it's imposible to play.
So it will be great if you add cfg support to locked xbox mode for terraria. For example, I launched Terraria, pressed smthng on controller, xbcm turned on and after pressing buttons on keyboard\moving mouse, xbcm still active/