Sorry if question Ended in wrong forum.
I have D365 online in one tenant and Exchange online in another tenant, Customer don't want to merge the tenant. All mailboxes will be using Exchange online tenant, and mailboxes are configured in CRM are only for Queues, no personal mailbox is used in CRM and will not be used in future. Users for login CRM are created as @orgname.crm.dynamics.com and licenses are assigned accordingly.
We now have to sync mailboxes (Queues only) with CRM but because both are in different tenant has become difficult to sync. As per MS documentation
(docs.microsoft.com/.../dn531050(v=crm.8)
Connecting Dynamics 365 (online) with Exchange Online in different tenant is not supported. I wonder how in rest of the world are connecting MS Exchange online and D365 online in different tenant or Organisations are forced to Move to single tenant, which i strongly feel won't agree with Microsoft Single Tenanat Strategy.