Yeah my first thought was that it was taken from heroes of the storm, but I'm not entirely sure since I haven't seen the actual model from hots. Looking at his animations for tyrael, it does look pretty low quality. The wing overlays are pretty cool though.
I don't know how easy it is to extract models and animations from hots (quick google search leads me to believe it's not very easy) and I don't know if the hots animations work well in d2, but I could give it a shot.
