Hello
You should be able to use the migrate command from the snapcenter server. If you try to do it from the server with the plugin; it will give an error. Below is the command you would need to run from PowerShell:
invoke-SCVOVAMigration -SourceSCVHost old-SCV-host-IP -DestinationSCVOVAHost new-appliance-IP -OVACredential appliance-credentials -ByPassValidationCheck -ContinueMigrationOnStorageError -