quarantine 'em

In French my site would be one or two points of light in an ocean of English or, arguably better, 404s

This is a much more highly-developed problem over at the SCP Foundation http://www.scp-wiki.net/ 

There is the English SCP wiki. And e.g. the Russian translations of the SCP wiki. But there are also original Russian SCP wiki entries

But that's a different problem, because the e.g. Korean SCP wiki is a separately maintained site which I can leave in its users' hands

And in fact maintenance/crosslinking of the English SCP wiki is also not really in my hands. I mainly just pootle around their IRC channel

So anyway, my problem is different from the other problems I've mentioned, and the solution is unfortunately WORK

I'm thinking probably a thin border at the top of the page where you can switch among multiple translations, if they exist