My idea is something like this:
Application: light switches, roller shutter control, switch on electrical sockets, etc.
I have been able to install in the base of larger light fixtures just below the junction box. Or in the inclosure of wall lights
+1 fit inside EU sockets
Spamming? No problem. If you want no discussion of your suggestion or opportunity to explain it, that is fine.
All that's really needed is a Sonoff Basic with gpio14 implemented as a switch. I suggested this about a month ago. Don't hold your breath though.
Why not just use one of the many wifi controlled box mount switches? Leviton, Ottim, TP-Link, Sonoff Touch and so on?