It is important to point out that, if a foreigner wants to move to a place out in the Japanese countryside and live there for a couple of years (or a couple of decades), they must have a valid visa for the entirety of their stay. (Foreigners who live in Japan usually live there via a Japanese work visa, they work for a company, and the company "sponsors" their visa. If they leave the company, their visa expires. ) You cannot get a visa to just "be a farmer."
The exception, of course, is to get a spousal visa, which does not require a person to be sponsored by a company. (In my previously posted video, about Rupert, he doesn't say it, but it seems he has a Japanese wife, which allows him to live in the Japanese countryside and be a farmer indefinitely.)
Here is a video of a German guy who married a Japanese woman, then they moved into her grandmother's house in the countryside, which had been unlived-in for years. (And I love the way he talks to his wife in English but she answers him in Japanese, but this might just be for the benefit of filming their video.)
"I moved to the most beautiful countryside in the world."