Configuring Encrypted vMotion With PowerCLI
Encrypted vMotion is a feature available in vSphere 6.5 onwards. It is something that is always used to secure vMotions of encrypted virtual machines, its a required option, but is optional for non encrypted virtual machines.
By default, non encrypted virtual machines will be set to ‘opportunistic’. If both the source and destination hosts support it (so ESXi 6.5 onwards), vMotions will be encrypted. If the source or destination does not support it, then the vMotion traffic will not be encrypted.