Wrong mesh transformation when importing animation

How to reproduce: When opening a .blend file from the "smash-ultimate-models-exported" repository (in my example the fighter/lucas/model/body/c00/lucas-c00.blend one), and then applying an animation using the import script (in my case the /fighter/lucas/motion/body/c00/a00wait1.nuanmb one), the mesh is not properly transformed around the regions of the shoulders. Screenshot_from_2019-09-03_23-10-20

This is independent from me porting the script to 2.80, I've also tried when the original script using 2.79b and the result is exactly the same. I know there is the warning about the non-aligned bones when applying animations, but I'm not really sure of what it means, and this happens even after applying the animation to the character right after having opened the .blend file, so I guess I didn't misaligned the bones or something.

Is it something that the import script skips?

Cheers,

Edited by Ghost User
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