How to use one master skeleton for multiple SK assets

I’m starting a project with my team and I’m missing some vital information for our pipeline.

My aim is to be able to have a single master skeleton (the UE_mannequin persona skeleton) for all biped characters. We have multiple characters with different anatomy that need different joint translations and orientations.
Your retargeting tool allows me to retarget animations between skeletons, but I’m missing the (maybe obvious?) step of how to manipulate, target and adjust each character to the master skeleton without actually touching the master skeleton itself.

If I understand correctly I need to change the settings for Translation retarget on the skeleton to fit my character, but that means I’m adjusting the settings on the master skeleton itself(?). Meaning I’ll affect all other characters.
Can I avoid that, and adjust my character without creating a new skeleton for it?

I’m using Unreal 4.14