There are 10 servers on Japanese server, ship2: Ur, is the place where there's a dedicated community on there. The reason why JP players were hostile toward Westerner was because the English players were assaulting them. Not to mention that was more than 5 years ago, happened on block20. JP players are actually nice, same for the Western players. At least nowadays when I do log onto JP PSO2 ship2, it's peaceful.
The translation group has been working on PSO2 JP translation for years, it's a dedicated thing already. If they were just to ban most of the westerner from playing PSO2 JP version, there won't be a community there at the moment. Also I've been there for 6 years and I do not believe any of my friends got banned for just buying AC. It's highly something happened on your end, ends up banned.