Tested the new leaked Super Smash Bros on my SXOS and it works perfectly. Even unlocked all the characters by changing some values of my save file in a hex editor.
Since it was a NSP, I decided to finally set up my emuNAND. Took a few hours with all the dumping and everything, but it's all good now.
When I boot into SXOS, it loads off an emuNAND that's stored on the microSD. When I boot without SXOS, it just loads the original sysNAND.
Both are independent of one another. I can keep all my offline games in emuNAND and use sysNAND for online play with real games and eShop titles.
Took the proper precautions by formatting my Switch entirely (once for emuNAND and once again for sysNAND) so hopefully I won't get banned. But if I do, guess I'll have to think about buying another Switch for online.
Here's emuNAND/sysNAND explained for the 3DS, but it's mostly the same concept.
https://gbatemp.net/threads/guide-a-...munand.410439/