Save IMAP email without active account

I used the default Samsung Email app that came with my Samsung Galaxy Note 10. I provided the IMAP details to get emails on my phone. I got rid of the paid account before I got the new phone. I don't have that account anymore. I can fully open and read all incoming and outgoing. It is doing this while offline, with no wifi or mobile data. Tech support says to screenshot them, but I don't have time since it has too many emails. How can I transfer the old emails from the old phone to a new phone or to a PC? Any suggestions?