Good mail server for selfhosting - Crony's Dungeon

So I’m migrating stuff from my old server to a new provider and only thing left is email. The problem is I used luke smith’s emailwiz script ( the script and setup itself isn’t a problem ) because it uses users for managing users with dovecot and friends to setup a mail server. So now I’m looking for a new email server to selfhost (preferably docker/podman) that in the future I can easilly migrate.Would also love if somebody has a reccomendation on how I could backuo and import emails from the old server.