

Not OP, but I have dumped my own collection of GameCube and Wii games.
The easiest way to do it is with a jailbroken Wii since it’s not hard to do. Once jailbroken, the dumping process is about 12 minutes for a GC game and about 20-30 minutes for a Wii game (I forget the exact time). So with that in mind, you can make a rough calculation for how long it will take to dump your collection.
There are a few unmentioned steps, like converting the games from .iso to .rvz to save on space, but it’s rather easy to get going when you have a guide to follow.
Jailbreaking the Wii U is a little bit more involved as it requires some “special” equipment. It’s in quotes as not many are going to have a USB A to ethernet adapter, nor a compatible model, but they aren’t all that rare either. But once it’s done you don’t have to worry about jailbreaking it again. Dumping Wii U games isn’t much harder than GC/Wii either.