Wii Fit U Miis
So, the first thing you might notice here is that Wii Fit U has all 60 of the CPU Miis that originated from Wii Sports: this is not a mistake.
You see, when creating Wii Fit Plus, the developers literally copy/pasted the entire game of Wii Fit and built it off from there. So when it came time to make Wii Fit U... they did the exact same thing again, meaning the original 60 CPU Miis from the Wii still linger in the files of Wii Fit U.
However! You can actually see these Miis in-game, in games like Free Run. This makes Wii Fit U the only game to ever put the Wii Miis back into a Wii U title!
And something even cooler is that there were 115 Mii data files found in the Wii Fit U Staff Credits folder (the last 4 were just duplicates of Yunyun) meaning not only do the 60 CPU Miis from Wii Sports make an appearance in this game, but so do all the 111 Wii U/3DS CPU Miis as well, in the credits! This makes Wii Fit U the only game in existence to feature both the Wii CPU Miis and the Wii U/3DS CPU Miis all in one game! How incredible...