I've created a few new Binder entries in GitHub for using Shared Mailboxes in the Graph API using PowerShell The Binder index is https://gscales.github.io/Graph-Powershell-101-Binder/ The topics covered are Accessing a Shared Mailbox folder and its Items Sending an Email from a Shared Mailbox The script for these entries can be found https://github.com/gscales/Powershell-Scripts/blob/master/Graph101/SharedMailboxOps.ps1
Pushing the Envelope in Messaging and Office 365 Development