I have been working quite some time on a project that  I called LapConnect. The idea was to let a laptop to control other PCs over USB interface. I.e. transferring video and emulation of HID devices. 

Check some videos on youtube - https://www.youtube.com/@LapConnect 

The main components is RP2040 having one hardware USB and one software USB port (PIO-emulated). This allows to connect two PCs together using just a single chip. The second part is famous MS2130 video capture chip that works well for USB video transfers.

Currently, I have an application for Windows , but  I plan to add Linux and MacOS support too.