VMware vSAN does not have any remote replication capabilities of its own. Stretched Clustering with synchronous replication is the exception.
Therefore in non-stretched setups it relies on external remote replication mechanisms like VMwares free-of-charge vSphere Replication (VR) or any vSphere compatible 3rd party remote replication application (eg. Zerto VR).
vSphere Replication requires the deployment of virtual appliances. No specific integration exists between VMware vSAN and VMware vSphere VR.
As of vSAN 7.0 vSphere Replication objects are visible in the vSAN capacity view. Objects are recognized as vSphere replica type, and space usage is accounted for under the Replication category.
VMware, vSAN [SDS]/7.0 U1, Enterprise
Remote Replication Type, Disaster Recovery, Data Availability