Is this a natural to say this in Romanian? I thought 'a visa' just takes a direct object. (Eu) te-am visat (pe tine). = I dreamed about you. (Eu) le-am visat pe animale. = I dreamed about animals.
It is indeed more common to leave out the "despre", but it's not wrong to use it.
By the way, here are some small corrections:
- Eu le-am visat pe animale. = I dreamed about the animals.
(here you refer to specific animals; maybe they were previously introduced by the context)
- Eu am visat (despre) animale. = I dreamed about animals.
(here you refer to animals in general)