Crypto illegalization depends on what country it is. So even though its legal for you to acquire crypto, if you want to buy something or send some of it on those people who lived in a total ban crypto then that would be useless. And also, here in my country, you cannot establish a company if you arent a citizen but you can open a bank account.
The crypto market exists in cyberspace by using the internet, meaning that transactions will not be known by anyone and do not violate anything.
Becomes illegal if transactions in a country prohibit the use of bitcoin but are used for payment or open trade. If in a country that legalizes crypto, of course there are no problems.
If bitcoin is illegal on your country , you can still use crypto only online because country or a government rather dont hold the online world , they dont hold bitcoin but its possible that they can ban some sites within their network or within the countries local ip . there are also sites that are illegal online and you can get into some serious trouble if you will insist to use and visit them .