Controlling Shelly devices using triggers

I’ve installed a Shelly relay which i want to use to switch off a specific device when input AC drops.

I’ve installed the Beta so I can now see my Shelly devices and switch on and off via the Cerbo screen.

In terms of automating it, is this something I should be able to do by configuring a Virtual Switch? It only seems to show the Victron Relays. or is it a job for Node-Red? If so, I have some learning to do!