>>415235446
do you still have the original smaller model? if so, what is the scale in Unity on the meshes or the Armature object?
On your newly exported model the scale here should be 1. On the old one it might be 100. This changes physbone/dynamic bone behavior regarding the "Inert" or "Inertia" property. You'll have to tweak this value specifically to fix this. Lower is more movement.