How do i hide a first person skeleton and set it so it still plays animations in third person?

So I have been working on a First Person Shooter and i have created a true fps view but for an even better view I want to have a hidden mesh (only arm animations) that plays animations to the Full body mesh.
But i can’t really find a way to implement this

For example: I want the First Person Arm Animations from the Shooter Game example to play in third person without the need of adding a new mesh.

Anyone know a way to do this?

Similar effect: Tactical FPS Prototype - Weapon Attachments - YouTube

In this video the creator has hidden a FPP skeleton and made it so that it plays animation to the full body mesh thus making the reload animations and ADS animations

You can just set the mesh not visible when it switches.