It's a bit older and made for UE4 but I bet you will get the trick. ;-) Turn the way it's done around by exporting as FBX-file to Blender and renaming the bones. Then back as FBX to Unreal Editor et voilà, no more retargeting nonsense.
Alles mögliche aus der Weltenschmiede mit Themen rund um Construct, Unreal, Games, Webentwicklung und Spieldesign. The aim of the game is to feel real good!