I have the same problem. Unable to play completely. I just purchased this on my Switch while we are on vacation and I feel fooled. I literally own Minecraft on every single possible platform. Can you comment on this one devs? At least confirm the bug. This renders the game unusable wihout internet for local splitscreen play.
Important info: I am trying to do this in local mode as I do not have Nintendo Online.
For the record, Minecraft exits with this weird error if it's unable to write to data directories. I unpacked the ZIP file accidentaly by root, executed as minecraft user and the error was the exactly same one. Beware!
Dupe of MCPE-79116