i did see a video on youtube where a guy changed out his light switch for a momentary switch with a battery operated controller. He basically just choc blocked off the wires and didn’t use them, but i can’t find it now.
Surely there must be a permanent live feed going to the switch and a switched live going from the switch to lights? The fibaro dimmers only need 2 wires.
There are full on switches, but again they need deep back boxes and seem to need 3 wire
maybe have a read through this thread for some ideas.