Hi Victor,
you can use the same means (SCP to /shared/images/ ) for any vCMP instance, host or guest. You can even transfer the images between them (log in to the "main host" and scp to the others), provided you have SSH access between the management interfaces. Starting with TMOS 11.6.0, there is also a synchronization of images and hotfixes between vCMP hosts and guests, meaning that the vCMP host will "propagate" its set of images and hotfixes to its vCMP guests. Hence, it would be sufficient to copy the image/hotfix to the host only.
Hope this helps.
best regards, Martin