Why EU? I would just go with IBKR, probably.
How would they even find out? But note that you would have to︁ file things for the freelance visa as well.
I know some people were asked to︂ file a UBO report including an organizational chart. For a freelancer! You will be dealing︃ with people with very low education, mostly from South Asia and the Philippines.
You would︄ have to check if you have to file corporate tax returns for the freelancer visa,︅ and you would also have to check if you have to register for VAT, or︆ if you can opt out somehow.
I really would recommend you to reach out to︇ other traders and just see what they do, how they are set up and why.︈
I would︌ rule out Estonia, but I know that Cyprus especially is very popular. Probably Malta would︍ work as well, and maybe also Portugal with the right structure.
I have heard that︎ you can even combine Cyprus with residency in Austria, but I don't remember the details.️
I also don't know how easy it would be for you to obtain residency there without an EU passport.
I believe some of them don't have capital gains tax? But maybe it's different with active trading.
In theory, it shouldn't be foreign income if you run things from that country, but in practice, especially less developed countries (Malaysia, Thailand for example) don't enforce this and will often treat all income︀ as foreign if it comes from a company that is registered abroad.