In our two bathrooms we have a switch panel with 4 switches: one for a light, 2 for heat lamps, and 1 for a fan extractor.
As we tend to forget the fan extractor I want to make this smart.
Something like 
It has to work well with Home Assistant. WiFi is fine, Zigbee would probably be better. Should not have a cloud dependency, I can't sell this stuff to my SO saying that she can't turn on the lights if the internet is down. I've flashed Tuya based switches and RF emitters with ESPHome using LibreTiny.
As it's obviously 220v I'd like to avoid Aliexpress stuff. Probably also needs a good IP rating as it's in the bathroom.
Any tips?
Use a shelly device, preferably Shelly plus or a gen3
They're designed for retrofit and have a huge amount of support