Although compatible with the “player Animator”, EMF appears to lock the position of the limb, making the ”player Animator“ movements play only rotation information, not displacement information,

In order to reduce the restrictions on the position of the parts, EMF action packages do not lock the position when the parts are not animated

Sample picture：
The gun animation is based on the "player animator", the EMF-enabled character action pack, this character pack has no arm action, although the arm gun animation plays normally, but the arm is forcibly fixed

This isn't an emf issue, this is controlled by the reeource pack you are using, at a guess you are using fresh moves, which specifically chooses not to affect arm rotations for mod compatibility

What i mean is the pack can be edited to support this mod

wooo!!!!
I did it!
Thank you for your answers!