I lived in Japan for a year. While I'm not a 100% bonafide Aspie, I still have my fair share of social troubles. I had trouble there, despite studying the culture for many years and being close to fluent in the language.
What I can tell you is that Japanese culture is somewhat Aspie friendly and somewhat not at the same time. It has its pros and its cons. I made the mistake of thinking that it was the place where I'd finally "belong". I found that I was mistaken, though it was a nice place nonetheless. When I came home, I was glad that I didn't live there permanently.
Reasons why it might be are that the environment is usually kept fairly clean, tiny, and quiet. Trains run on schedule most of the time and there is a certain level of exactness in the way people go about their lives. New technologies are usually welcomed with open arms. Everything is pretty strict and structured. There are lots of rules to follow, including lots of 'set phrases' when you speak. If you memorize those, you can pass for competent in many situations.
Reasons why it might not be are that the communication style is anything but straightforward. People do not tell you the truth very often there. It is almost always said indirectly, especially if it is an insult. There are different levels of politeness depending on who you talk to. If you speak to a superior, you must be polite. Sometimes even tiny gestures can be construed as rude. A lot of the communication that goes on is left unspoken. Often it is not what you are doing but what you are not doing that gets you into trouble.
As a foreigner, you will be given some leeway that they probably would not do if you were Japanese or were of Asian descent. If you are, then you may experience an even greater amount of prejudice there because people will assume that you know the rules and are therefore breaking them knowingly. You should know better, in other words.
Additionally, there is also a lot of bullying that goes on, at the highschool level, college, and later in the workplace. Most of it is hushed up, so if you experience it, there is probably not much help available. Same goes with cases of domestic abuse or racism.. much of it goes unreported to the police.
I feel like I would've gotten along better if I were NOT as aware as I am about the language and social rules. Everyone's experience will be different. I enjoyed myself overall and I love the country still, but it was by no means paradise. No place is perfect. So long as you understand that, you will do fine.
Anyhow, though... I would urge you to go there and see for yourself. It's always good to make up your own mind about how it is over there.
_________________
I don't suffer from insanity. I enjoy every minute of it.