Half the time here I find that the panels haven't been marked at all. That's not too much of a problem on the typical older 4-fuse installation, but where extra sub=panels and circuits have been added, it can take a long time to trace out.
Even where descriptions are present, they're often just not explicit enough, inaccurate due to later modifications, or just plain unintelligible. The prevelance of the ring circuit and just a couple of lighting circuits here means that individual room circuits aren't all that common, but where they are used there's also the point that "Johnny's room" undoubtedly meant something to little Johnny's family, but isn't very helpful to whoever lives there now.
Most domestic panels these days come with sheets of peel-off/stick-on labels for the breakers. While making it very quick and easy to label the breakers, they still don't really provide more than very basic information. There are usually stickers just marked "Sockets" (along with a symbol), maybe "Upstairs sockets" and "Downstairs sockets" if you're lucky. That's not very helpful if the circuits don't neatly divide into first and second floor.
I've never seen anything other than English used here, although I've never lived or worked in any of the areas where we have a high percentage of non-English-speaking immigrants. By the way, the U.K. is actually officially bi-lingual:- Welsh is an official language in Wales.