Smash Wii U do other GC controler adapters work for smash?

[Malcolmnex]

I have bought smash wii u digitally and i have three gamecube controllers and ive noticed there third party Gamecube controller adapters available that are cheaper. would they work with smash?

if not, would the official gc adapter be sold by its self?

 

[Ultrashroomz]

If you're talking about something like the Mayflash adapter, then no, that wouldn't work.

The official adapter can be bought separately for $20.