NSP files are essentially the digital version of a game—the format used when downloading a title from the Nintendo eShop.
The only legally defensible way to obtain a ROM was to dump it yourself from a cartridge you purchased. Switch Roms For Yuzu
Yuzu does not come with any games. To play a title, you must provide: NSP files are essentially the digital version of
Since Yuzu’s shutdown, forks have emerged: you must provide: Since Yuzu’s shutdown