Spouse of Japanese national abroad

Hi!
Could really use some advice as I have a whole lot of questions regarding my current situation. Been searching this forum and the internet but haven't found a similar enough problem...
I am married to a Japanese national and just got my first 1-year visa. As it turns out my husband will be transferred abroad to SE Asia for the next 3-5 years come spring and I will of course accompany him. I have concluded that renewing my visa during this period will be quite impossible (but I will still try for record's sake) although we will be going back to Japan at least twice a year. If anyone knows of any sunshine stories with different outcome - please share :-)

Now...he is employed by a Japanese company and will therefore stay on as resident but pay less taxes in Japan. His company is atm also covering my national insurance and pension etc... (I am currently active housewife ;-P)
One question is...when my visa expires (and wont get a renewal), since we are still married, can I have a national insurance/pension ongoing in Japan - through his company...? We wont have much coverage where we are going so the company is recommending us to go to dentist, do check-ups etc, in Japan during our 2 trips/year.

Where do I start with all this? His company is new to the phenomenon of foreign spouses and I am feeling overwhelmed and insecure regarding all of this. Do I need to contact each authority one by one or is there a one place I can go to for answers in these matters...?

What else do I need to consider regarding my chances of visa renewal when abroad and/or once we return? Anything else I missed that I should be aware of before going? Moving from one foreign country to another without knowing the laws and rules of either can sure make your head spin...

Any advice in the matter would be really helpful. Thank you <3

.when my visa expires (and wont get a renewal), since we are still married.....

It is mandatory to renew your visa before it expires.
It does not matter if you are married or not.

Since you have a unique situation it would be better to contact immigration how to renew your visa abroad since one of the requirements is that you are living in Japan.

Very unusual. You are not living in Japan so why do you need a status of residence for living in Japan? You actually don't (because, as you say, you will only be visiting) - and probably it doesn't matter (IMO). You are not drawing on Japan resources or paying tax (Japan govt wants your money), so as a non-resident (living overseas) logically it becomes irrelevant.
When you move back to Japan, you have a long history of being married - that is when it counts.

Hi! I`m almost in the same position!
Me and my husband got married in 2018, got 1year visa until febuary 2019, we moved to the USA in January 2019 for 3years due to his work! Still working for the same company but it is a big international company.
So my spouse visa expired last year and now I am just a normal tourist when we visit Japan!
When we will go back we have to apply for my visa again.
I'm also a housewife like you and have health insurance paid by his company.
And also the pension is as far as I know still paid by his company regardles if my visa status. Best thing is to let your questions answer by his companies human resourse people and if they cant answer everything it is their duty to get all needed information, they are Japanese and can call around and search around better ;)
Good luck!