I would love this! I'm a completist when it comes to animal color morphs, and would love to be able to take my albino snakes from one zoo to another.
I read somewhere that the reason we can't move them is that it would further mess with the finances mechanics, making it possible to essential move money from one zoo to another, and thus making the financial challenge (such as it is) less important. But I'm not sure if that was an official intended reason or just a fan theory composed as an after-the-fact justification.
It may also be an asset problem at a technical level, if for some reason shared items are more difficult to code or more resource intensive than mechanics that are specific to a given zoo.
But I'd absolutely love if it was possible!