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.