Suggestion for the Eset anti-spam filter: Mark mails as spam, based on own rules for individual X headers.
My e-mail provider has decided no longer to add a note to the subject of e-mails classified as spam or to change the subject in any other way.
Instead, spam mails are moved to a folder on the server that cannot be retrieved via POP3 (IMAP is not an alternative). However, I have created a rule on the server that moves all mails to the inbox that are not sorted out by other filters. Rules for X headers are not possible.
Now, of course, I get the spam mails in my inbox, which are now only marked as spam in the mail header via "X-Spam-Flag: YES" and are not recognized as spam by Eset even with the extended antispam database.