Dear P28036,
Greetings. Thank you for reaching out to Microsoft Community. We are glad to assist you.
As per your description, l understand that you would like to create an ideal rule which can delete all incoming messages containing "xxx.edu" except for messages containing "1.edu" OR "2.edu" through "6.edu".
Please feel free to let us know if below rule meets your need or not.
For further support, it is suggested to contact support agent within Outlook for Mac. Our support agent will help you find a solution.
- To contact our Outlook for mac dedicated team, go to Help > Contact Support.
- Enter your Name, Email, issue that you are experiencing and select Send.
- After opening a support request, a help icon will appear next to the New Outlook switch to provide easy access to the current request.
Additionally, when a support agent provides a response, a red badge will appear on the help icon along with the macOS notification.
Please feel free to let us know if they find a solution for you or not. We look forward to hearing from you. Stay safe and healthy.
Kind Regards,
Tammy | Microsoft Community Moderator.