Two identical skeletons, but in different poses. How can I assign a new skeleton to a skeletal mesh if the poses of the two skeletons are different?

How do I replace the skeleton of a skeletal mesh(boots) with another one, provided that they have different poses? (The hierarchy and the name of all the bones are the same)

I understand how to do this with animations (via retargeter), but what about skeletal mesh?

  1. This is the old skeleton (it need to be replaced with a new one)

  2. This is the new skeleton. I want the boots to use this skeleton instead of the old one.

  3. This is the result I get when using “Assign Skeleton”

As you can see, the poses of these two skeletons are slightly different: the position of the legs and arms is different.