One bone is moving somewhere else after retargeting

Hello I have exported Mannequin skeleton, moved them slightly to match the model and then rigged in maya. No problem about it. But if I import an fbx animation file to UE4 and retarget the default mannequin skeleton to this for using default assets like jump walk run animations, this bone going somewhere else.

I am right clicking the default skeleton and chosing “retarget to another skeleton” option in content browser.

But I am getting this. And weirdly only the right arm is doing it, left arm is OK:

So I can not retarget and use default UE4 animations. Can somebody point me to right direction please. Thank you in advance.

The bone you are showing is hand_r, not lowerarm twist.
remove lowerarm twist from the retarget parameters or make sure its retargeted to the proper twist. My guess it is badly mapped since the other one works.

Sorry I have changed the picture now for correct bone. Thank you for your quick answer but I double checked the mappings they are correct. Then I tried to remove it from mapping list then it worked. But I have to find why it is working on the left side and but not on the right side. Would you help me on this please. This thing drives me nuts. I have uploaded the file here if you are interested.…ew?usp=sharing

Open the skeleton, enable the Show Retarget settings. check what that specific bone is set to.
IF it is set to animation, that’s why. set it to skeleton.

Keep in mind that nearly ALL of the base animations are in fact 100% wrong. export them to something and you’ll see that the translation of several bones are wrong across the board.
If you are using the aim stuff from marketplace, the right wrist is in fact offset wrong on almost if not all of the animations.
Thus, for it to work the re-targeting options have to be set to “skeleton”

Or you can export the animations and parse them through something like my add-on to get them fixed. I don’t suggest it tbh, you are better off putting the time into making better animations on your specific rig.
But in case you want to give it a try Bone Breaker: Unreal to Blender

IF the above doesn’t work, maybe put together a blank project with just the skeleton/mesh and 1 animation.
If I import the rig myself it’ll work for me…

Thank you very much