Yes, you can use Edizon to cheat on games played via cart. Edizon executes the cheat codes by modifying the data loaded into the console's RAM, which is independent of the ROM source (digital or cart). The saves are stored in the console's storage rather than the cart. As far as I know, saves cannot modify/corrupt ROMs. I would generally advise against using Edizon on your sysMMC if you would like to utilize Nintendo's online services later on. This is a ban risk. The Switch collects telemetry data whether or not it is "online" and sends that data to Nintendo upon connecting to their servers.