Properly licensed CTAs can charge whatever they desire. Attracting and keeping clients is another story
Management fees, yes. Performance fees... conditionally... that is, (1) clients must be "accredited investors", and (2) minimum 12 months performance before performance fee can be earned.
Not sure. I don't recall anything about citizenship nor residency. That you are on U.S. soil means that you are subject to US law... that probably includes securities law as well. Suggest you contact the SEC directly. RIAs are covered under the Investment Advisers Act of 1940.... often referred to as "The 1940 Act".
What if you aren't in US soil? By the way, I'm just looking to get my RIA designation, to give a professional image, even if it's not needed outside the US.
If you are not in the USA, I suspect the 1940 Act wouldn't apply to you. It also seems logical that your application to be RIA would therefore be rejected.