In Breeze Amidst the Forest, Volume 1:

"The dragon graced by Anemo was born in the high heavens." While the word heavens is often associated with the divine, I think this is one instance where it's more about the sky itself. And high sky can mean stuff like exosphere or thermosphere, indicating that Dvalin was born in those places.

And we already know that Vishaps typically prefer living in places their associated elements are rich in.

Geovishaps live deep in the mountains and under the ground.

Bathysmal Vishaps (Hydro Vishaps) chose to escape to the bottom of the Dark Sea when they found the new world order insufferable.

Fungi (Dendro Vishaps) can be found in places full of greenery.

Holawaqa Ngoubou (Advanced Qucusaur (a Pyro aligned subspecies of Saurians, who themselves are descendants of Pyro Vishaps) who bears the most resemblance to traditional dragons) is found in Huitztli Hill, which is a ridiculously hot place.

We even have cases of IRL animals who spend a lot of time midair! Common Swifts can spend months without landing. They sleep, eat, shit, and mate while flying. Anemo Vishaps may behave similarly, only even more radically: they don't land ever, spending their entire lives so high up in the sky, even their wastes don't reach the earth.

Also, sidenote: Man lore sub's rules are kinda confusing. I couldn't post this there.