The Ambassador and Force Sensitive Emergent have access to the Indistinguishable talent, which upgrades the difficulty of any checks made to identify the target.

Are there any rules regarding which skill is used to identify a character or is this left to the GM?

Generally, Perception would be what I would use against them.

The Ambassador and Force Sensitive Emergent have access to the Indistinguishable talent, which upgrades the difficulty of any checks made to identify the target.

Are there any rules regarding which skill is used to identify a character or is this left to the GM?

I've used relevant knowledges for notables.

I've used perception to match up to a datafile.