I’m using blender 2,79 and C4 client. Importing animation into Blender is bugged and I advise against that, especially for character’s animation. For monsters it „somehow” works. But you don’t have to import animations to export mesh to UE.
When you attach shoulder to your armor you have to assign vertex to the bones in Blender. The shoulder’s bone has to have the same name as vertex grup. (Don’t try to rotate your mesh in comparison to the bones. In fact don’t care about the bon