One of my email addresses is apparently part of a spam database – and there linked to the wrong name “Nina Steiner”. So any mail that makes it through my spam filter and contains this name is definitely spam and should be marked as such.
However, with the Spamassassin integration, Plesk Onyx does not provide a feature that allows you to define your own rules for content analysis.
Spamassassin itself supports this feature, which is why I show how to use it on a Plesk managed system.