The current beta build of Minecraft Bedrock on Xbox one crashes every time you swim, fly, and sleep on split-screen co-op. I think it's something to do with animation changing.
Also chests appear invisible and mobs turn invisible but weirdly only to one out of 2 players.
This is all I've found on this so far though.
Please keep it to one issue per report. Most of these issues are already reported anyways.