What requirements? The only real requirement is to have someone sponsor you. Everything else, including having passport and no previous history of war crimes,

What requirements? The only real requirement is to have someone sponsor you. Everything else, including having passport and no previous history of war crimes, raping and pillaging for 5 years also applies to other visas anyway. It's also not H1B type of slavery, there are not quotas, you can change employer whenever your want and not even lose fancy tax ruling. Work visa is the easiest way.