Working remotely in JP as spouse visa

I'm based in JP now and have my zairyu card as a spouse of Japanese national now. I'm in online interview with an overseas company (not based in JP) for a specific job that I can do remotely work from JP. However, the company seems wanting to hire me as contractor and ask me to solve the matter of tax payment, insurance etc by myself. Currently my health insurance and pension are being covered and deducted from my wife's company and salary. For the salary income, the company asks me to provide the account bank for remittance in JP, and they can remit it every month.

  1. I'm a little bit confused in this matter as the company isn't based physically in JP and not a Japanese company, can I do a remote work like this in JP as a contractor based on contract renewal from that overseas company?
  2. How can I solve the tax income in this matter if there's a remittance happened from overseas to my account bank in JP?
  3. The bank in JP also will ask the purpose of each remittance happened frequently from the overseas bank account, especially when I receive USD. How could I explain this?

by Unfair_Buy2933