As Visual Assist has been one of the most essential extensions of VS, I think it is necessary to make VA support other interface languages besides English. It would help more users to use VA comfortably. (Moreover, users should be able to choose which languages they will install or use.)
We have an open feature request to support other languages:
case=619
I've added your interest to the case.
BTW, which language would you like to use Visual Assist with?
Actually I prefer English (Because translation may be terrible if there's no active excellent maintainer). But some of my Chinese friends expect to have Simplified Chinese (zh-CN) localization.