It’s been there all along and most of us just didn’t notice it! Apparently, Tracer’s RECALL ability hides a song within the ability that was just only discovered recently by the Overwatch community. Check out this video by Force Gaming which summarizes the details of this awesome Easter Egg.
Yup, her Recall ability is actually a reversed sped-up song. Thanks to Reddit User rfilmyer for investigating and discovering this little gem. It’s an awesome little easter egg about the game and I really do like it when things like these, even the small things, get looked at. You gotta love the Overwatch community with how dedicated they are to things like these (remember how things were back during the Sombra ARG?).
Maybe this should be counted as part of the official Overwatch OST? :p