The legality of video game emulation is a nuanced subject:
Assume you have acquired a legal, self-dumped copy of the game. Here is the workflow. zelda breath of the wild cemu rom
This is where the magic happens. Once you load the game in Cemu: The legality of video game emulation is a nuanced subject:
Important Disclaimer: This information is provided for educational and informational purposes only. Downloading or playing ROMs of games you do not own is illegal in many jurisdictions. You should only dump your own legally purchased copy of the game from your Wii U console. Assume you have acquired a legal, self-dumped copy
Within CEMU, go to Options > Graphic Packs > Download Latest Community Packs.
For Breath of the Wild, enable:
Cemu is a high-performance, experimental emulator for the Wii U console. It was initially released in 2015 and is notable for being one of the first emulators capable of running commercial Wii U games at playable framerates. It is developed in C++ and is available for Windows, with experimental builds for Linux.
Nintendo is notoriously protective of its intellectual property. The company holds a strict stance against unauthorized emulation that facilitates piracy. They have stated that downloading ROMs and using emulators to play games without purchasing them constitutes copyright infringement. They have historically issued DMCA takedown notices to websites hosting their ROMs.