opening an account without any documents is possible, yes. nevertheless, you need some valid personal information (especially ssn etc.) whereby "valid" does not necessarily mean "real". and you will have to pass some kind of simple verification process, for example sms authentification or such. but in fact, as soon as you try to move a certain amount of money with that kind of accounts, the bank will ask for further verification (KYC) for preventing money laundering etc. etc.
making it short: the sooner or later you will need documents!
so, in case you consider buying such bank accounts from someone: make sure you can handle any later requests by the bank ... and you WILL receive requests for sure.