Does sense allies lets you tell if someone is a ally?

Afterall if they were not a ally, you cannot tell where they are with the eyes close. I feel like the proper response is this is cheese and gm will not allow it.

Trying to figure out what fifth level feat would fit my sword and shield fighter, who has the back story of being a medieval peasant isekai to DND in sort of medieval RL setting who kind of being a little stressed by all this magic. Maybe I just grab courteous comeback