You can hack the wii mode of the wiiu via using the smash stack hack but you will need a legit copy of super smash bros brawl to do this as well as a sd card. It is also not permanent so u have to do it everytime u turn off or get out of the wii mode
I did try this for myself with the original wii and it worked but havnt tried it with the wiiu but according to the internet, it works so...
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