On AU's serviceportal you can create a shared mailbox
You need to add both a primary and secondary owner of the shared mailbox. Supply auid in the form auxxxxx
Syntax rules: There are certain requirements for naming a shared mailbox and email address. You can read more about the rules here
Displayname: The name shown when receiving a mail from the shared mailbox. The display name must be appropriate for the purpose of the shared mailbox.
Email address: Specify the desired email address according to the syntax rules.
Purpose: Shortly describe the purpose of the shared mailbox
On behalf of: It is possible to send your request on behalf of another user. You can search for the user's name or auid in the form 123456
Once you have submitted the form, you will receive an email confirmation of the ticket creation. When the shared mailbox creation is finally approved, you will receive a corresponding email confirmation.
Once the functional mailbox has been created, the members must add the mailbox themselves in Outlook, see instructions here