Netherbeak flies in an erratic, high-altitude path around a wide swathe of Azsuna. It is stealthed and is only detectable by Track Hidden once it gets close. A good place to wait is to hover a distance above the temple on Rhut'van Peak. Netherbeak should eventually fly by and aggro to you. Then land on top of the building and tame away!
*Level scaling: In Shadowlands most NPCs will scale with the Hunter's level, within the constraints of their level range. Hunters can tame regular NPCs up to 2 levels higher than them, but can only tame elite NPCs of the hunter's level or below.