Layered Blend per Bone in a Skeletal Mesh agnostic base animation blueprint template

hi, i had some questions about your implementation. Is your ALI_Upperbody - Upperbody linked anim graph a template as well, so does it choose a skeleton. I just wanted to know whether the templateness of the blueprint is maintained. Like can you use multiple skeletons with this blueprint template as long as they are humanoid.

In my case, I want to use fabrik to ensure proper placement of the left hand on guns and I am having a problem as the fabrik node requires access to a skeleton to work.