Which P.R.O is recommended and has the least bureaucratic process of sign-up for foreigners?

I’m thinking of affiliating with a P.R.O but not from my country (for reasons). I know it can take a lot of time to receive earnings if the P.R.O is not in your country but it’s OK. What I really hate is filling out forms, mailing letters and all that bull****.

I just need assurance that if the miracle happens and one day a client buys a broadcast license, I won’t miss out on my earnings.

So according to your experience, which one has the least bureaucratic process of sign-up for foreigners? Can it be done online or is it necessary in every case to use the good old mail?