Novel way to save old emails due to server loss

Due to a security vulnerability with cPanel, I completely lost the emails on my mail server (including the mail accounts themselves).

I still have all the emails on my Mac mini in Mail. I know that if I connect Mail back to the recreated mail accounts on my server, all the local emails will be deleted.

Is it possible to update the settings for the local mail boxes to isolate them from the server and then create new mail boxes that connect to the server for mail going forward? I realise that I'll have mail in two different places but this seems to be the easiest way to preserve the old emails and still work with new emails.