Exactly this. I use Shelly relays in the switch boxes and use the physical switch as an input to the Shelly relay. I have a couple AliExpress zigbee relays too that work well.

The trick is with three/four way switches where the smart relay needs continuous power and to be physically located at the end of the chain where power is actually switched to the light or outlet. Took me a while to figure that out but an SPDT relay with 120V coil solves that. The problem is space: fitting the relay to provide continuous power to the smart relay and the smart relay itself into a standard junction box with a physical switch and all the usual mess of wiring is not easy.

“I moderate heavily. If someone is rude or abusive, their comment isn’t published. Unless it’s really funny.” :-)

Gang of Four?

“Nothing is perfect” Is a hell of a way to minimize the enormity of the issue. Like wow…