HomeBridge will present a HE virtual switch to the HomeKit ecosystem as a regular switch. Whatever automations you can do with switches on the HomeKit/Apple side can flip the virtual switch on HE...although an Apple TV may be required.
I made a virtual switch in HE for a HomeKit-only door lock:
From HE, I can lock/unlock the door by flipping the virtual switch.
On HomeKit, I made two automations to lock/unlock the door when the HE virtual switch flips on/off.
On HomeKit, I also made two automations that flip the HE virtual switch if the door is locked/unlocked by key, knob, or code.
Since I'm generally happy with the HomeKit arrive/depart detection, I made two more HE virtual switches (that turn right off) triggered by HomeKit automations "whenever anyone arrives home" and "when the last person leaves" for triggering automations in HE.
I was running HomeBridge with Wink for a few years now, and just spun up a Docker instance of HOOBS on a shared Raspberry Pi this weekend. I highly recommend HOOBS over messing with editing JSON files on HomeBridge for ease of setup.....
