Portugal D7 Visa from Japan

Hi all,
I’m thinking of moving to Portugal using D7 visa.
I believe I am aware of the standard D7 requirement like 7,980 annual income proof, but I’m not quite sure that I am qualified with my remote work salary and saving amount(Which is enough to over the 7980 line for next 5 years). And yes I do have few passive income (Dividends) to support me but it doesn’t quite much by itself.
Having enough fund in my saving account with few dividends can count?
And I see many people who already have D7 visa are working remotely from Portugal, how do you guys care of the income tax?
Is there are any similar case you supported before?
Thank you so much for your support any information is valued for me.