In a lab scenario, a vEdge running 19.2.3 must be controlled by a vManage and vSmart running the same or a compatible version (typically 19.2.x). Mixing major versions (e.g., vEdge 19.2 with vManage 20.x) is generally not supported and will lead to control plane connectivity issues.

to initialize this vEdge image once it's uploaded to your hypervisor?

Because Cisco SD-WAN software is proprietary, there is no public "direct download" link. To obtain this specific file legitimately: Cisco Software Central : Visit the Cisco Software Download Entitlement : You must have a valid Cisco Connection Online (CCO) ID