The wiki page for translation request says that, to find requests for French translation, I should search french text + translation request. Most of what you'll find under that combination, though, are images almost entirely in (untranslated) Japanese, with maybe one line of (already translated) French text. I can't remove french text, because the image does have French text, but I also can't remove translation request, because the whole thing hasn't been translated - it just that the text needing translating... isn't French.
e.g.
post #6879283
post #6650995
post #5210444
Ditto for commentary request + french commentary; most of the stuff in the French commentary request queue really needs Japanese commentary - the one sentence of French was already taken care of ages ago and now it's just languishing in partial commentary limbo.
e.g.
post #3860127
post #5723016
post #5618737
To stop mostly Japanese (and to a lesser extent Korean) from gumming up the translation queues for other languages - the obvious solution to me is to split up translation request, check translation, commentary request and check commentary into language-specific tags, e.g. translation request (french), check translation (french), commentary request (french) and check commentary (french). Then deprecate the language-unspecific tags so that new posts wanting translation done are forced to specify which language needs work.
And I would be happy to put together that BUR, but the obvious problem I foresee this causing - and why I didn't immediately just go for a BUR - is that it implies a UI modification is needed. For example, the checkbox to add check translation when submitting a translation wouldn't mean anything anymore if translation traffic is supposed to be re-routed to check translation (french); likewise with commentary. It seems like the dialog box would need to include a list of languages tags and you could check off the ones that no longer need translation work, while leaving other languages (Japanese, usually) checked on as still needing translation work. But, I don't know how much of a technical challenge that poses.