Was just wondering if anything was stopping me from grabbing the 2018 Smash Ultimate GC Controller and plugging it into a Wii or Wii U, or even a Gamecube.
Thanks
Thanks

Nothing. The Gamecube Controller is the "same" as it was for the Gamecube. The reason I put quotes around same is because while its designed to be the same as the original controllers, it doesn't quite function like the old ones. Reportedly, some of the new controllers have drifting issues or cause you to turn around randomly. Why that is may be due to the large gap in production time between the old and new controllers.