After the latest 3.0 firmware upgrade, the HORI Pokkén Tournament Controller and Brook Universal Fighting Board are now both compatible with the Nintendo Switch.
For the popular Pokkén controller, this is almost definitely because of the latest announcement for Pokkén Tournament DX. It is worth noting that the Pokkén controller has shown compatibility in odder places in the past:
pokken Pad is just a usb controller that works with anything that lets you use a PS3 controller. Works with ps4 skullgirls @Circa_CatFight pic.twitter.com/ruzG0zNadE
— Chris Medina (@MischiefKaos) October 6, 2016
By making the Pokkén controller work with the Nintendo Switch — whether intentional or not — the Brook Universal Fighting Board now works with the Switch, too. Brook was working on compatibility for the Switch in the past; it sounds like their job got a lot easier.
Source: My Nintendo News