I speak zero Japanese. I've met a lot of immigrants here in the last couple of weeks, and it seems that you can get to a working level of Japaneses within a couple of months. After that, it seems that working for a Japanese company IRL is the biggest determinant of becoming fluent.
I've heard that the path from temporary visa to a more permanent one is somewhat straightforward for a self-employed person if you're able to show moderate revenue from Japanese clients.
The good news it that Japan seems to be in desperate desire of skilled foreigners, and announced plans this week for a digital nomad visa: https://www.japantimes.co.jp/news/2024/02/02/japan/society/d...
I've heard that the path from temporary visa to a more permanent one is somewhat straightforward for a self-employed person if you're able to show moderate revenue from Japanese clients.