This is a simple loopback MIDI interface - through an RP2040. I created this project as I needed a loopback MIDI interface on a Windows laptop that I did not have administrator rights to. I hope you find it helpful :)
Below: picture of RP2040LoopbackMidi working with the professional lighting software, grandMA3, with taped paper on the keycaps of a keyboard. A Python script takes the keycodes and sends to the loopback MIDI port which grandMA3 reads for key shortcuts.