Right before Andro's Reversal shuts off you can send your fully charged shot at him (easy to headshot him when he's trying to position for Reversal) and hit him before the green things are gone. Pay attention to the sound of his Reversal.
When Drogoz is airborne, try snapping almost directly in an upward direction then snapping to his location horizontally. I do this when playing and seem to easily headshot him mid-air on a regular basis. example: https://youtu.be/DGVWJDimNv4?t=83
When Makoa is stunned, aim a bit lower on him to hit his head hitbox. Once you learn the location of his stunned head hitbox you'll see it's very easy to output high damage on him during his being stunned.
When you see him use Billow, wait a little while before transporting away because he cannot cancel the ability and transporting away too early gives him time to close the gap on you.