It's going on my todo list, can't promise it'll make it.
To be honest, I don't even use Openhab yet. I fiddled with it before and the opportunities are crazy, but I would put it on a separate raspberry pi?
I evaluated OpenHAB. It's cool, but not cooler than Home Assistant. Also it's not a core feature, you can run OpenHAB from the OpenFLIXR included docker.