I used the Sunshine game streaming software and the WiiU homebrew port of Moonlight to get game streaming working on a WiiU gamepad. It’s sort of like a bootleg Steam Deck, and it works surprisingly well, but it mostly just made me want a Steam Deck.
If you can’t find an original adapter, I can confirm this one works. Most of the other ones I had laying around wouldn’t work. I had to search for this one. It was only $15 when I got it in January 2025, not sure why it’s $25 now
Its any Ethernet adapter with the AX88772 chipset. I would also go for getting it from any other online seller :P