In a Supernatural!Verse, Wings would be an angel, as would Skyfall and Fallenbird.  They'd be the vessel ones ((like Castiel or Gabriel for example)) Starclan people would be angels too, but not all take a vessel

I'd imagine Lion being once used a vessel for a demon, then after that he became a hunter. ((Psst. Lily is his badass hunter child, most of his kids may be hunters?))

I imagine dark forest cats as demons. Tigerstar being essentially Satan himself.

Storm, Onyx would probably be hunters too, or some sort of nephlim because they're dad is an angel, as is their sister. Swan, Freckled and Fledgling would be nephlim too.

For some reason I see Darth as a shapeshifter? Or a special kind of demon?

I imagine most normal living cats would be normal mortals or hunters, and medicine cats would be physics who can speak to spirits/unvesselised Angels, as well as those people who will know exactly what kills what.