Best advices get Maewing on Fjordur :

Teleport to Asgard NE

You'll spawn exactly in the area where the Maewings are

There's a lake nearby they are sometimes underwater

If not net gun your Maewing and knock it out on the ground (not many aggro dinos in the area)

If underwater good luck! (U can sometimes knock them out (underwater knock works) cuz they get stuck in the lake)

Make sure to up this tip so every one can see :)