I am having trouble making weapons appear in hands on specific stances similar to the 3D era games of Mortal Kombat. I have three moveset files that can help changing the stances, but I do want the weapon appear in character's hand to appear for the weapon stance (3rd Stance), I found the trick that would only help me so far is adding a hitbox to the mesh and turn off visibility, it works well as the weapon would not show as default, but the body visibility part only works in moveset files (mostly attacks) and only show during a move but does not show anymore after the animation played. Pretty much it does not show on idle animations for a weapon stance since Idle Animations is the only one that doesn't have move file option for me to put body part visibility in use. Here is the progress so far:
https://streamable.com/8piy4f

Here is the Idle animations showing no "Use Move File" option:
https://ibb.co/T83XpLy

Here is the stance system I'm trying to go for:
https://streamable.com/skuqhc

Could anyone help me out?