Forti manager HA on Hyper-V with different subnet and devices located on different GEO location?

According to this document, https://docs.fortinet.com/document/fortimanager/7.6.2/administration-guide/568591/high-availability , it should not be a problem.

The primary unit and the secondary units can be in the same location or different locations. FortiManager HA supports geographic redundancy so the primary unit and secondary units can be in different locations attached to different networks as long as communication is possible between them (for example, on the Internet, on a WAN, or in a private network).