Advice For Tattoo Artist Moving To Japan

"Japan immigration REQUIRES (mandatory...) a degree or 10 years experience for a "work visa"

Not even close to true. If you get hired upon graduating from a Japanese university or technical school you need 0 years of experience.

I came over with a student visa, studied Japanese for 2 years, moved on to business school, studied and graduated after two years, and then got a work visa in humanities working in real estate.

3 years and 10 months later, I'm currently in the process of applying for the citizenship. I went to the final interview 4 months ago, should receive it within the next few months.

Yes, when you graduate from a university and get a degree. And then after that get hired by a company which can offer you a job with a valid visa category attached. You've confirmed that what everyone has been saying on here is true.

When you graduate from a university, that's fine. OP isn't doing that or planning to work in a field with a valid visa category
Op wants to go to a language school(which anyone can do) and go straight into work from there into a regular job with no high school diploma or without graduating from a university

Not even close to true. If you get hired upon graduating from a Japanese university or technical school you need 0 years of experience.

graduating from a Japanese university = getting a degree...
you need 0 years of experience = my answer was having a degree OR 10 years of experience which was meant for people WITHOUT a degree like OP.

You said nothing new here. You just twisted the answers but saying the same thing we said.