I recently did a portfolio on the Adobe Portfolio builder. When I got to the point of publishing I realized I had been logged in with the wrong account the whole time (I had purchased PS years ago with one address but now paying the Cloud subscription with another one) - so now I can't publish the portfolio as the older account only has a basic license. As building the portfolio was a bit of a too long and frustrating process (it took me ages to realize it's just not possible to do sub-galleries and then rebuilding everything) I don't really feel like rebuilding the whole thing on the new account again.
So is it possible to maybe 'export' or transfer the portfolio data to my paid account? Or can I connect the two accounts somehow so I can access the data from both ones? Or is there any other way avoiding the rebuilding?
No. Sorry. Not possible. Now that you've done it, you're an experienced user. It should take no more than 15 or 20 minutes to put together a new Portfolio under the correct account.
Pick a layout theme.
Create a couple of project pages.
Add a few images and add some text descriptions.
Publish site.
That's all there is to it. Just focus on the basics. You can always go back and refine it later.