@seadude Thank you for reaching out to Microsoft Q&A. I have checked with Engineering team, and they have confirmed that Currently Send and Receive MSS using Azure Communication Service is not supported.
Your feedback is noted, and I have relayed the feedback internally to our product engineering team.
We also have a feedback item on this, if you wish you may upvote and Comment on the Uservoice post - All of the feedback, you share in these forums will be monitored and reviewed by the Microsoft engineering teams responsible for building.