This article is a follow-on to Volsync article but introduces a relevent use-case for using Submariner.
A. Installing Submariner Add-On to Spoke1/Spoke2 clusters
B. Enabling Service Discovery
C. Changing VolSync to use ClusterIP Instead of LoadBalancer
https://github.com/kcalliga/submariner https://www.myopenshiftblog.com/acm-add-ons-submariner/