With this component you can calculate the alpha between block and normal weapon animations. In the weapon block component you need to set your head’s socket if you have a non-unreal engine skeleton (Picture 2). You can also choose the block distance you need.

Picture 2 - Weapon Block Setup

In the component I calculate block distance and then use it in the animation blueprint to blend between blocked and not blocked states (Picture 3). 

Picture 3 - Anim BP blocked distance