Idk if you're using Ryujinx but I'm gonna assume you are. So the instructions for installing on Ryujinx say to replace the 'contents' and 'exefs_patches' folders in the Ryujinx 'atmosphere' folder. You can do that first for the Yo-Kai Watch 4...
I was confused at first too. Since this mod only works with version 2.2.0 I acquired that update NSP. I updated the game in Ryujinx by right-clicking the game icon and clicking "Manage Title Updates", then "Add" and navigated to the version 2.2.0...
You can buy drm free games / music / ebooks, and if you keep backups of your data (like documents and family photos etc), then you shouldn't lose the game. but with a disk, your toddler could put it in the toaster and there goes your $60