I've never heard "kitty-corner" or "cattywumpus" in the UK.

I don't know what the UK word for an all-ways-at-once crossing is - it's the usual type so maybe nobody thinks of giving it a name. In New Zealand when I was there they were called "barnes dance" crossings (al least by some people - I may have had an atypical experience since my father was an architect who had been trained as a town planner, so I may have picked up plannerese rather than Kiwi).