i followed this tutorial …Unreal 4 Tutorial: Animation Retargeting with Different Skeletons - YouTube i clicked on duplicate animation and retarget option ,it duplicates , but the problem is ,first , the animations (ue4 animation) didn’t duplicate in the folder where i imported my character ,and second , the animations were all black , i was able to apply the animation but the result was wierd , the view was dark and there was some movement , like the view was a broken pieces , ps : i used blender , and my character was huge in size if this helps , but i don’t think that my character size impacted the animation duplication
So the reason their not going in the same folder as your character is because when you choose duplicate and retarget, that window that opens with the two characters on it has a section at the bottom where you can set the location for it to duplicate the assets to, the default location is the Content folder. As for your character, if you didnt already, when exporting the animations, choose ASCII as the export option, and turn the scale up from 1 to 100 (idk why but the defualt export size in ASCII is 100 times smaller than unreal).
I made a tutorial on importing animations from mixamo skeletons which shows how to do this correctly. Your situation might be different since its a custom character but this might help UE4 adding root motion animations from mixamo - YouTube
still having the same problem , and the animation is still black