Is an 11.5-inch interior wall with opposite switches permissible?

no.. normal red bricks...

if it had been drywall like in the standard, it probably would have been a little less, I think.

Hi,

we are planning a dressing room between the bathroom and bedroom, so our bathroom will be quite small.

At the moment, we only have a thin wall in between, and it’s already somewhat annoying.
We work in shifts, and it does bother us; you can even hear when toilet paper is being torn off and various other sounds...

So, I don’t think the sockets will be the problem, more likely the whole wall.

Best regards, Olli