How would Methi`s owl form look like if she form-shifts into one? Well, here`s your answer and I admit, she`s kind of strange for an owl like that, . In that form she is unable to speak, only squeal, click and hoot. She is as big as normal adult barn owl.
The 1st picture is how she would look like as a totally normal wild/tamed owl, just casually hunting rodents. Her real nature is revealed through the hooting though, as she sounds like squealing baby girl and occasionally makes clicking sounds with her beak.
The 2nd one is her being in the service as an Army Carrier Owl. The canister on her back normally hides messages, but can also hide ampuls with poison and the razor sharp steel talons were set on her feet by the owl tamers she`s in service. With them she can hunt rodents with more efficiency and defend herself from those that try to capture her. She can even kill a human if she digs them in the right place.
The last, 3rd picture is her look when she is "revealing" from her soul the lifetime of ghosts and undead she meets, which literally means she is out of her body in soul form. That`s also her look if she takes the time machine and goes into the past that is other than her own time. You know where is she from the background This specific form has its own theme song: [link]
And deliberately making this visible, so everyone can see it!