OH HEY! Are you me?
I can kill Tracers usually, but I struggle with Genji because of all the jumping.
I watched a video from Overwatch Central interviewing Boombox who is a top Zen player last night, I found his tips useful.
https://www.youtube.com/watch?v=OCttIv34C1E
I'm no where near GM, so I usually try to stay close to a tank if I know I'm going to get dived on. If my tank can simply visually hide me from the enemy coming head on, I can use the discord orb or just the discord lock diamond reticle place my shots.