While the standard version requires you to keep the /apps/genplus-gx folder on your SD card, a properly built WAD can act as a "forwarder" that looks for the emulator data in a specific location, or in some rare cases, installs the entire emulator to the Wii’s internal NAND memory (though keeping ROMs on USB/SD is standard).
To install the emulator as a channel on your Wii menu, you will need a modded console with a WAD manager. genplus gx wad
You might ask: Why go through the trouble of making a WAD when the Homebrew Channel version works fine? While the standard version requires you to keep