Dr. Hax on Nostr: My own design, but you can make one yourself too. ...

My own design, but you can make one yourself too.
https://gitlab.hax0rbana.org/public-repos/ps2x2pico

I did not write the code but I can attest that it works for all the keyboards I've tested and most of the mice, however my mice don't have compatible scroll wheels (see the issue in the upstream GitHub issue tracker)