Trigger rule when ZigBee device registers on network

There are drivers for Generic Zigbee devices that support presence. I would think you can try the one for the Generic Zigbee Outlet and see if it works properly, if it does you can then create a rule that if the device changes from not present to present as the trigger.

Here's a link to the topic of the drivers with download links... [Release] Generic Zigbee Drivers with Presence and Recovery