Not sure if you've already transferred or not yet, but I also live in Japan, but am American. There are plenty of major, massive English linkshells, and more than a few bilingual ones too (I run one myself, but it's currently more or less just me, as most of our main members got new jobs, moved, etc, and haven't gotten back in yet). I generally feel like the Japanese are more accepting of foreigners (as far as pugs go) than you might otherwise expect on a normal JP server. I'm sure the JP player base is aware of what Tonberry is for us, and I regularly see people using the autotranslate before even establishing language.
And even if there isn't anyone using the translater, I find bilingual people are far more common than you'd expect, so there's often a lurking translator-in-waiting.