IF
You are a tax resident in a country without CFC rules which would make your offshore company tax liable there by the mere fact that you as a natural person are tax resident there
AND
Incorporate in a country with zero corporate tax for companies incorporated there - most known tax heavens, for example, BVI
AND
You have a director in a country where this would not make the company tax liable in this country because you have a director there (could be BVI as well)
AND
You do the business activity from another country without declaring permanent establishment and you are aware of the consequences,
then you will pay no corporate tax but you will still need to pay personal tax on the dividends you withdraw from the company.
For the permanent establishment please keep in mind that:
1) this could be a vague interpretation, for example if I am not wrong OECD states that permanent establishment needs to last at least 6 months.
2) The other thing is that some countries may have very aggressive tax office which may hunt the permanent establishment and try to prove that it is there, for example Spain is well known for their aggressive tax office and I would not do this there. For bigger amounts of undeclared tax you can go also to jail in Spain.
None of Bulgaria, Cyprus or Slovenia would give you tax-free incorporation. I said from lawyers in this countries I have stayed with the impression that it could be fine not to declare permanent establishment there.
If you need to work on such setup you need to start looking into tax heaven jurisdictions. Different jurisdictions serve different needs but for crypto trading for example and probably in most cases almost for everything in my humble experience BVI is the best both for incorporation and for a local director there if you can afford it.
To my knowledge bank account itself would not make a company tax liable in the country of the bank. However if in this same country you are doing something obscure like hiding permanent establishments or being tax resident there it is not a good idea to have the bank there.
That being said it is extremely difficult and nearly impossible to open bank account for offshore jurisdiction and if it is for crypto trading your options are limited to probably a few banks in the world which would require very big deposits. It's virtually impossible.
PWC has plenty of useful info. You just switch on the respective country and you can see the CFC rules, PE rules, personal and corporate residency rules, the tax liability etc...
