Yes – legally, you can dump your own cartridge using a homebrewed Switch for personal backup. However, distributing that NSP or using it on another console is illegal. And again, without the physical kart, the backup is useless.
An emulated version would just show a static image or crash. So again — no working NSP exists for this game in a meaningful sense. Mario Kart Live- Home Circuit Switch NSP Descar...
: Fully customise course rules, including engine speed, music, and specific gate hazards like Piranha Plants or Chain Chomps. Local Multiplayer Yes – legally, you can dump your own