We are configure many vSphere Replication Servers in the proection site. The vSphere Replication Server may located in the different network VLANs.
What't the network requirement between these vSphere Replication Servers?
Does the VRS require the Layer 2 network connection?
It doesn't require L2, but if you're sending lots of replication traffic you should provision a new vmkernel port on each ESXi host on a dedicated TCP/IP stack tagging it for replication. From there, because you have a dedicated netstack with dedicated routing tables and buffers, you can route that traffic using custom routes if need be.