Ajman, probably others as well.
Just be aware that business banking in the UAE can be difficult/impossible if you don’t have your own office (flexi desk). But you could probably just bank elsewhere ( EMI) and only use a personal bank account in the UAE.
There are also mainland companies offering “freelancer visas”, but that’s not the same thing. They hire you as an employee, so you get an employee visa and need your “employer’s” approval for everything. In the freezones, you should usually get an investor visa, so you’re your own boss. But of course you’re not allowed to do business with UAE customers in the freezones, so if you want that, you need to get a mainland visa. I’m not sure if it’s legal to circumvent that buy using an offshore company if the work is done in the UAE, probably not. If you work for UAE customers from outside the UAE, I guess it would be fine.