While I started my prototyping using a Nucleo-F303RE board, I switched to STM32G0 line recently and now have a working custom board based on STM32G071 :)

All bells and whistles working:

and ABB binary output understands very well to our commands:

Leason learned today: Do not let a KNX+ wire hang around. 30 volts accidentally touching a GPIO will kill your STM32 in a millisecond.