From what I can tell, Odin should still work on US devices, but I don’t think that its been kept current with devices and Android versions. Most of what I’m seeing is support for Android 9.0 and later, which is pretty out of date at this point. That being said, it’s not something I’ve messed with much, so I’m happy to defer to someone else with more direct experience.
The GameCube, Wii, and Wii U all use the same basic setup: PowerPC G3 CPU and an ATi/AMD GPU with an upgrade each generation. They are, in effect, very similar to how the PS4 and Xbox One started their own current trends. In fact, the Wii U can run GameCube games natively with some effort, and Wii games out of the box.