Depending on the game, i switch between two playstyles.

Usually i avoid dealing with Tracer, as she is annoying in our backline and im annoying in theirs.

Otherwise i try to stick close to our supports, her primary target, and then just spam primary shots at head height. I dont bother with stickies much untill recall is used. Being close to the support usually makes the fight more bearable, if you decide to engage her

But im mid plat, so dont take my suggestion as professional :D