Unable to send emails to Sharedmailbox using SharePoint workflows

Hello Everyone,

Have you guys ever faced an issue when you try to add a online Shared mailbox to SharePoint workflow? I am not sure even if this feature is available or not? Can anyone know if Microsoft is allowing SharePoint online workflow to send email to "Shared Mailbox"? 

Note: All our online Shared mailboxes are in block stage. Is this because of that they not showing up while adding them to "SharePoint workflow" . Is there any alternative to add them to workflow without even unblocking them?