Hi,
Could you please be specific on your requirement? As per my understanding, if you have Exchange servers in 2 sites in a single DAG then you can perform datacenter switchover/failovers. Disaster recovery for the Exchange servers can be achieved using DAG. Kindly correct me If I misunderstood the requirement.
https://learn.microsoft.com/en-us/exchange/high-availability/manage-ha/switchovers-and-failovers?view=exchserver-2019
https://learn.microsoft.com/en-us/exchange/high-availability/disaster-recovery/disaster-recovery?view=exchserver-2019
http://cloudexchangers.com/exchange-2019-disaster-recovery-part-1/
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