Store virtual machines in a container without leaving traces on the OS

[fsflover]

Looks related:

Encryption of app vms?

This may be a silly question and I don´t see it elsewhere with a search. I rather suspect that this isn´t possible, but, can I encrypt individual vms? My system is encrypted in a general sense of course on startup and I can encrypt standalone vms such as Kali, but what about the vms that I create as app vms? Can they be encrypted? Sorry if this has been covered elsewhere. Thanks