How to use 8bitdo USB Adapter with WiiU Pro Controller - YouTube
Amazon.com: 8Bitdo Gbros. Wireless Adapter for Nintendo Switch (Works with Wired GameCube & Classic Edition Controllers) - Nintendo Switch : Everything Else
This tiny USB adapter lets you use a PS4 controller with a Nintendo Switch - The Verge
Playing GameCube games on Wii with 8BitDo controller - Nintendont - YouTube
TIL the n30 pro 2 is compatible with the Wii wheel! : r/8bitdo
The SNES Classic & Wii Classic Pro controllers both work on Mario Maker 2 using the 8BitDo Gbros Adapter, both have ideal dpads and feel right at home : r/NintendoSwitch
Official OEM Nintendo Wii U Pro Controller Compatible w/ Nintendo Switch 8BitDo | eBay
Gbros
GameCube Controller Adapter for Wii U, Nintendo Switch and PC USB – Lexuma
8BitDo 8-Bit Wireless Adapter
8Bitdo Wireless Bluetooth Game-pad Receiver USB Converter for PS3 PS4 for WII U PRO Switch RR Adapter - Walmart.com
8Bitdo Wireless PS3/4 Wii Mote Wii U Pro Controller Bluetooth Adapter for Nintendo Switch, Windows, Mac & Raspberry Pi Nintendo Switch Accessories - Newegg.com
Thanks to Raphnet and 8bitdo I can play 8/16 bit wirelessly on the Wii in 240p : r/retrogaming