Does the prince really need to be from Portugal or Sweden? Her cousin Rupert of the Rhine is completely free for the job.
Would prefer someone from there, yea. Though didn't think about Rupert. He would've being over twice her age though by he point they got married (if they waited til she was 17 at least), and tbh, would it be a good idea for it to happen?
Probably should mention what I'm planning really. Essentially, Elizabeth escapes parliamentary control to the Americas. There, after her fathers execution, Charles "II" death at Dunbar and James' refusal to agree to Anglicanism or tolerance by the colonial officials ruling in the crown's name at the time, as well as preference to remaining in French court, lead to her being crowned Queen (in exile). This made the middle and southern colonies, Virginia and Carolina, split from the Northern (New England, which remained under Parliaments, and Puritan, control (Cromwell having died by this point and John Lambert in more or less control)) and became independent Kingdoms, in union with that of "the United Kingdom of Greater Britain".
So trying to find her a suitable husband, that wont lead to a even bigger mess down the line. Why I'd prefer Portugal or Sweden, as both had colonies near, but weren't able to really push for claims against the Commonwealth, or a noble from any country, that was at least close to royalty.
I even thought about using exiled English/Scottish nobility, but I know even less about them at the time, or the "requirements" to choose. Hell even thought about using a Dymoke, just cos of my llove of the Sparhawk book series. Dymokes are the family that usually spawn the King's/Queen's champions, that, quite literally, throw down the gauntlet at coronation dinners.