There was an article in the EAA magazine a few years ago about an EAA chapter in the Tokyo area.
Apparently (at that time) you have to land at the same airport that you took off from, the paperwork was insane, etc.
Having worked in Japan many times over a 15 year period, albeit not in aviation, I never saw a GA aircraft.
Just driving around in Japan is really fun, slow, frustrating, but beautiful, especially in Hokkaido where the engineers havn't destroyed every road cut with concrete.
Enjoy Japan but don't hold your breath hoping for a flight.
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