Good luck! It's worth the effort, and handy if you manage to pull it off as everything is horrifically backed up in the federal offices here due to Covid.
I tried for some time while overseas to register for an account, using my mail forwarding address in the USA. It would not allow me to register. (It recognized it as a mail forwarding service.) The system will try to take you though some serious ID stuff from your credit report to prove you are who you are.
I haven't been able to get it set up in the six months we've been back in the States, either. Not sure if it's because I have a precautionary credit freeze with all the big credit bureaus or not. I did phone their tech support and was told that I'm "Almost there" but that they couldn't tell me any more for security reasons. So if you can't set it up, maybe the following from them will help -
https://www.ssa.gov/help/global_statement7004.htmlEDIT: I just gave signing up another try (not having done so since before Christmas). Now it is going to send me a code by USPS that I have to use to log in. Supposedly it will be here in 10 days. So, if you do try to sign up, be sure your inputted address is for someone who will be good enough to email that code to you.