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There's Human Aliens. It might be good to start from there.
https://tvtropes.org/pmwiki/pmwiki.php/Main/HumanAliens
Call a Smeerp a "Rabbit" would cover Rocket Raccoon specifically.
If not for this anchor I'd be dancing between the stars. At least I can try to write better vampire stories than Twilight.
Intelligent Gerbil when aliens resemble a terrestrial creature.
Rocket's not actually a good example, as he is in fact an Uplifted Animal in both his comic book and film incarnations- he's just very deep in Furry Denial in the comics and doesn't know what a raccoon is in the films.
Do we have a trope for when an alien is mistaken for a human being, but not due to shapeshifting? For instance, a Kryptonian is on Earth, undisguised, and a human thinks she's a human since Kryptonians look just like humans? (Just to be clear, it doesn't have to be humans; it can be other things too, like how Rocket Raccoon isn't a raccoon—or so he claims now and then—but still is mistaken for one.)