Actually, maybe here's a (custom) solution: Run mains wires to an enclosure with...

Actually, maybe here's a (custom) solution:

Run mains wires to an enclosure with one of these:

And controlled & powered (the mcu, not the relays) via this:

Hence avoiding a separate esp board/mcu for every switch/device, and just using a single relay board for 4 at a time.

Still a bit of a pain to drag mains to one location, might be better if this was individual relay boards with equipment wire running to each..