There is no type of visa for remote work in Japan. You could obtain an Intra-Company Transferee (ICT) status as a representative in Japan to engage in market research, or some similar activity for your company in the U.S. Under the ICT visa status, you may be able to work for the U.S. company remotely while you are not allowed to engage in part-time jobs for others.
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How can I move to Japan while working remotely for a company outside of Japan?
I got a job offer from an international company, where I can work 100% remote. If I do so, is it possible to get a visa when I will move and pay my tax in Japan? If not, is it possible to get a visa for any part-time job in Japan? I have no university degree, but I graduated from a vocational school in 2009, working for 9 years in IT support.