Automate turning off display of Nest hub?

Hi all, I have several Nest Hub Max devices around the house which I would like to turn the screens off whenever the house is unoccupied. You can currently say “hey Google, turn off” to each device individually and the screens will do just that. Unfortunately you cannot say “hey Google, turn off the screen on the kitchen display”, the command must be given to the device itself. I’ve tried “Assistant Relay” but because of the above limitation it seems like it’s a dead end.

Has anyone found a way to do this? You can run a routine on Google assistant to turn off the displays at a certain time but it’s convoluted and you can only do it based on time, not occupancy.

I’m trying to do the same with the new google assistant SDK integration but does not seem to work…