Yeah it really depends on the game, the region you get it from, and which version you buy as some games will have a "retail" release and a special one from a specific publisher (like ININ Games for titles like Wonder Boy Asha in Monster World). Sometimes it's a first print thing too like with Sonic X Shadow Generations or releases that come from a box set. You have to go out of your way a bit to get some of them but I think it's worth it.
I've been collecting Switch games for a while so I'll try and post a few that I know of:
This one is red for a good reason LOL
Not a reversible, just a misprint
Pre-order bonus for Asia version:
Slipcases:
EDIT: I'm adding this as a fun bonus, it's another misprint