Danielpeles I’d like to add what others are saying if your’re still thinking about it. Out of the box there is no support for the Wii U BUT you can adapt it. You have to talk to both Nintendo and you need to go to Epic’s custom licensing Other licensing options - Unreal Engine
If you want to develop a game with Wii U in mind you can do it, you just need someone with the know how to go into UE4’s source and make it compatible with the Wii U hardware.
For reference, the Wii U has 1gb of usable RAM and about 360 gflops of gpu performance, not sure about cpu