Maybe one more stupid question, but …
As having two different RPi:s (Hass.IO) running another with ZHA (Elelabs ZB Shield) and another with Zigbee2mqtt (CC2531) and being very satisfied for both - - can you run them in same RPi using both entities in common automation.
Now just some devices are only supported in one of those platforms - so that would help in my system a lot?