My plan is to move to the EU and I assume I will want to get a local account to handle local transactions. I would not necessarily need a local brokerage account if I can keep my investments in the US, I would just need to work out the reporting requirements for local taxes.
A lot of the details will depend on my work situation at the time (local employment, US remote, or retired). I’ve started a list of things I will need to figure out, but am mostly just adding to the list right now since any potential move is still several yeats away (at best).