Outlook, Exchange Online, Auto Reply to each message

Hey Guys, 

Here is what we would like to do. We need to make it so that anytime a shared mailbox receives an email that it auto replies, to that sender and all other messages from the same or other senders. Setting an OOF as you know only responds to the first email that a sender sends. 

In the past we would simply setup a shared mailbox in outlook (Added as the only mailbox in the profile) and then setup Auto-Reply with rules/template. that worked as expected. 

However with modern auth and with basic auth disabled I am not able to add the shared mailbox to an outlook profile, i have full access rights to the mailbox. 

How might we go about accomplishing the above requirement?

I would open a ticket with Microsoft support,. but this would be like a 3 week ticket and they still wouldn't be able to fix it. 

Robert