Visa path for remote work & study

Hi, I'm from the UK and considering a move to Japan for a year (and then see how it goes). I intend to continue working remotely for my UK company and also enroll in a Japanese language school there.

I have enough points to get through on the highly skilled worker visa but I can't find anywhere that tells me what is permitted, the only information is that it's better than other visas because it allows "various activities".

Is this visa a good route to look into further? As a temporary resident not importing my income I don't think I'll be paying Japanese income tax either, so I wonder if I even fall under the category of working in Japan. Maybe a student visa would be a better option?

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