I think you wanted to post this in the Proxmox Mailgateway forum, or? 
(moved it)
For that you can add a new "What" object, e.g., let's call it "Blocked Display Names".
There add a "Match Field", this allows to match arbitrary email header with a "Regular Expression".
For example use
me\.aeServer.*?[^"'<>\s]+@ to match any occurrence of "me.aeServer" in front of the "real emails" @, it's just a heuristic though, false positives could in theory be matched, but rather unlikely.
Use that What object to create a new Mail Filter rule in Incoming (or In and Out, depending on your needs) direction, maybe take a lower priority than the whitelist so that that is consulted first..
Add the "Block" action and the "Blocked Display Names" What Object you just created and be sure the rule is enabled.
You should be able to simply test it by sending such a mail through your server.
When initial testing this you may want to use the "Quarantine" or a "Notify Admin" action, to avoid problems if something does not works out and be able to do some "dry-run" tests.
