I think you can't avoid tax unless you change residence to another country because
your tax authority may request you to present them your sublet contract!
Then what?
You mentioned you have to rent space from legal entity A for 1000 / year. right?
Then you let this space to legal entity B for 90K / year .
What if tax authority in your country ask you to show also the contract that you have with legal entity B?
In your case who will be the legal entity B in the contract
that will pay you 90K on your bank account?
Can you explain more in details please?
For common "small" people is difficult to escape the parasitic systems
that are feeding on the working class and which you may know are designed
for the rich to become richer.
Only the rich have totally legal means to "lower" their taxes legally.
we cannot fight the system in our country, so being a good taxpayer may be safer, maybe the tax is charged big but that is also because the money we have is also large, in the business of buying and selling bitcoin, we can still seek profits from our business , even if there is a tax but it is comparable to what you get.