The problem is that Trading 212 (like many other UK brokers) does not permit you to have an account if you are a US taxable person (either by residency or citizenship.) Similarly, most US brokers do not allow you to have an account if you are not resident in the US. This creates some problems. I think it would be good to investigate the possibilities with a US broker that does offer accounts to both UK and US residents. The one I know of is Charles Schwab. I know that Interactive Investor can do in specie transfer with US brokers. But they do not allow US residents or citizens (even if resident in the UK) to have accounts.