Is it feasible to create a true multi-language video file with visual localization?
I can't give you a complete answer, but it's certainly possible in theory to create 'playlists' (for lack of a better term) that call out a sequence of clips, most of which are common to two or more lists, with localized clips being different in each list. 

This would require a player that understands these lists, so it wouldn't work for general distribution since no common, general purpose player I'm aware of can do this. But I've written such players -- not for this purpose, but with the same result -- so I know it could be done. Audio sync might be the trickiest part.

I hope someone else has an off-the-shelf solution. There's a whole lot out there and more every day. Good luck.

EDIT:

It later occurred to me that this is exactly the function of an NLE (non-linear video editor) when previewing: create a timeline onto which you place audio and video clips, then play out the result without creating a new file. If this suits you, there are free or low-cost NLEs available, including LightWorks.