It’s time for something more complicated than rewiring premade stuff. After joysticks and gamepads, next thing that you can’t replace that easy is the mouse. After searching the net for a bit I found the solution on Aminet. Small device with microcontroller (MCU for short) that translates signals from standard PC PS/2 type mouse to signal Amiga understands. I also found versions with USB connector, but it’s actually a bit of deception. “Real” USB mice aren’t supported. As far as I understood there are too many variations in USB implementations to implement USB support with these small microcontrollers. It is possible, but it would need more powerful MCU and would subsequently cost more. It could be made with simple MCU but then it would work only with mouse type that it was tested with during development, even so far that it could happen to work only with that specific model, not the whole brand.