[= ;183425]
Depending the animation, the issue of the bones can appear or not
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Ok, now I know why it worked with the idle animation 
-> havent found a fix for the walking animation, but when you select your skeletal mesh - Object - Apply - Location/Rotation/… it should fix the problem with the deformed hands.
As a temporary solution you could do a right click onto the bone in the skeletal mesh editor - “Recursively Set Translation Retargeting Skeleton” But I will try out some more stuff 
