Central europe here as well: We have light switches that are press to toggle and spring back in our home.

The UK and many ex-colonies that also maintain plug/outlet switches seem to generally use down for on, while the US/Canada/Central Europe often use up for on.

Especially annoying are the posh toggles, unnecessarily popular in some European countries (e.g. CH) that don’t have any physical indicator of on-off status.

The lack of any affordance whatsoever on buttons, switches and appliances in Switzerland drives me absolutely insane

This becomes confounded if you have multiple switches for the same light though.

Maybe they should be installed sideways.

Here in USA, single-gang switches have "on" and "off" embossed on the switch, so the state is shown based on the position (oriented up is on). Multi-gang switches have no embossing.

It’s fine for multi-way switches, and probably even better than confounded switches, but as I mentioned they’re unnecessarily common which in this case means that they’re often used (at least in some settings in CH) for single-switch setups as well. For instance, my apartment had around 8-10 push switches of this type, with only 1 that was a three-way switch.

And in other places (e.g. Japan), the switches are left/right. I think right is On.

Sometimes it can even be either way, because there are two switches and toggling one of them toggles the light in any case; they essentially act as a XOR circuit and are most commonly seen in corridors.

More like a not xor, since you typically need to have both in the same position, not in opposite positions.

The apartment I live in has switches that turn the light on in its down position in some rooms and switches that turn the light of in its up position in other rooms. Fun!

You can fix it quite easily by pulling out the whole switch and setting it in the box the other way.

But by now I've gotten so used to it that I don't want to :)

Or when you cheaped out on workforce you could get some of them up, some of them down :D

And some not working at all.