These variables, grouped under the general list personality section, control some public information about the mailing list.
mylist in mylist@example.com.  The posting
    name is always presented in lower case, with alphanumeric
    characters and no spaces.  The list's real name is used in some
    public information and email responses, such as in the general
    list overview.  The real name can differ from the posting name by
    case only.  For example, if the posting name is mylist, the
    real name can be MyList.
moderator addresses (see below).
owner addresses.  For example, when
    you email mylist-owner@example.com, both the owner and
    moderator addresses will receive a copy of the message.
    Subject: This is a message
and the subject_prefix is [My List]  (note the
    trailing space!), then the message will be received like so:
    Subject: [My List] This is a message
If you leave subject_prefix empty, no prefix will be added
    to the Subject:.  Mailman is careful not to add a
    prefix when the header already has one, as is the case in replies
    for example.  The prefix can also contain characters in the list's
    preferred language.  In this case, because of the vagaries of the
    email standards, you may or may not want to add a trailing space.
p=reject or p=quarantine policy, see the
    dmarc_moderation_action description in section
    2.7.
If set to Munge From, it replaces the From: header address with the list's posting address to mitigate issues stemming from the original From: domain's DMARC or similar policies and puts the original From: address in a Reply-To: header.
If set to Wrap Message it wraps the original message as a MIME subpart of an outer message with From: and Reply-To: headers as above.
Note that this option is simply an aid for anonymization, it doesn't guarantee it. For example, a poster's identity could be evident in their signature, or in other mail headers, or even in the style of the content of the message. There's little Mailman can do about this kind of identity leakage.