I found this. Might give a bit insight since a blue name responded.
I’m bringing this up specifically because it is impossible for someone to get your IP address from within Overwatch. We do not use any Peer to Peer connectivity in Overwatch - as both your game connections and Vivox go through our centralized servers.
Currently, some Party Chat on Xbox Live goes through Peer to Peer, but this is a problem that Microsoft is currently working on . Because Peer to Peer connections do not occur within Overwatch, your best chance at avoiding such an attack is to never join an Xbox Party Chat Request from someone you do not trust. If you only use Overwatch in game chat to communicate, you will not have your IP exposed, since all traffic goes through a centralized server.