>>6673032Overwatch's lore is pretty flexible. It's more about the characters themselves having vibrant and interesting personalities and interacting in interesting hypothetical ways rather than a hammered-out story/events. So just have fun with it, maybe you can read up on D. Va and figure out if you would have fun owning her and posing her with the other two.
In canon:
Tracer is a fan of
D.Va as a celebrity-streamer.
Mercy and Tracer have been on missions together, both being part of the "original" Overwatch before Tracer got time displaced (there is a short comic you can read about it, Overwatch Uprising).
I can't think of any canon interactions between Mercy and
D.Va but in the game of course they can be on teams together or against.
Also there might be in game voicelines any two of the three have each other with but i forget.
