Unable to play game with my wife.  Hers has the same error.  A quick web search will show that other people are experiencing the same issue since at least December.  Get it fixed or refund people that bought the Switch Edition if it's not a priority >,>

Update: Sometimes the Sign In at the bottom left says, “Sign in to Microsoft Account”, while other times it randomly says “Sign in to Nintendo Account”.  It’s bug city, please fix.

Update:

Seriously... you got rid of the Nintendo Account option?  I needed to make an XBOX Live Account and use it to log in to my Nintendo Switch... this is ghetto and shady as heck.  Get it together please.