BFT Rigel 5 - Electric Gate Control Box

That’s the standard use for the micro switches, including the Fibaro and the Aeotec. The relay is always powered from the neutral, so if there is no neutral at the switchbox you typically have to put it at the ceiling rose. So the physical wall switch is just toggling the relay, the relay controls the current to the fitting, but the relay always has power so that the radio could hear the next “on” command from the network even though the light is off.

All of that said, it shouldn’t be used with Hues. Smart bulbs need to be able to control the current to themselves, so they should never be on a dead line. You can greatly reduce the life of the bulb if you are cutting power to it all the time.

There are several alternatives. The most popular in the UK is probably to use the devolo battery operated switch. Some people put it in a mount over the existing switch. So there is a physical switch right where you want it, you also have full control from SmartThings, but the bulbs themselves are always on power.

You’ll find discussion of all of these in the UK lighting FAQ. See option 3a.