Decreasing Workload

Hello,
I'm a graphic designer on a 3 year work visa as an employee at a company in Tokyo.
I was wondering if anyone knew if it's possible to decrease the workload from working 5 days a week to, for example, 2 days a week. My monthly salary is 380'000 so reducing my workload would theoretically be 152000/month. I would then proceed to work on a freelance basis for other Japanese clients on the other 3 days.
So my questions are:
- Will my company have to report my change of workload to the immigration office and if yes will the immigration office be ok with it?
- Will it be legal to work as a freelancer besides being employed from an immigration offices perspective? Or will I have to switch to a self-sponsored visa?

If anyone has had experience with anything similar I'd be happy to hear how you dealt with it!

Thank you!

- Since your current employer decided to employ you on the current terms (5 days a week, @ 380,000 yen a month), based on which you were granted the work visa, if they make a material change, which I believe it is, they should be reporting it to the immigration authorities.
Now if the current employer wants to keep you, but somehow is unable to keep you full-time due to COVID, then there are some relief measures that they can take. Is that the case?

- Since you are on an employer-sponsored work visa/resident status, you cannot engage in other work without obtaining a separate permit from the immigration authorities. (Whether immigration authorities grant you this permit, seeing that you are not in substance really working gforh that employer any more, is another question.)
Self-sponsorship is possible only after a certain number of years on an employer-sponsored work-allowing resident status, and I believe youfd need to show pretty good track record. Please note that there is no specific type of resident status/visa called gself-sponsored visah in any case. (Please search this forum for other threads on gself-sponsorship.h)

Hey AK,
Thanks a lot for your fast reply!
And thanks for asking, but it's not about Covid but rather that the company and I agree that it makes sense that I only work a couple of days a week and freelance with other companies the rest of the week.
But reading your post it seems like it's not as easy as I thought!
I will try to talk with the lawyer who helped us with getting my visa to see if he has any ideas/solutions.

Jamie,
If you can rely on an immigration lawyer, yes, please do ask them.