I'm gonna just comment as I watch this, and edit as I notice things.
Nice reflexes on the Sym, she was playing really far away from her team and picking her off so far away from the Mercy probably snowballed into you winning that first objective.
That Sym played horribly.
Lots of people have trouble on second point of assault maps, especially in this meta. I would have suggested that you ask the Roadhog to go Zarya and get an ult combo of some kind for second point attack. Nice work on second point overall though. Your comp sustained much better than the enemies', you hit enough shots to justify staying Hanzo, although if the enemy had any more tanks I would have considered swapping.
Pretty good attack. On a side note, snipers are actually better on attack than defence, because pick-offs are more valuable, although snipers are usually still quite bad on second point assault. We can talk about this later, the point is don't listen to people that immediately hate Hanzo or Widow.
32 eliminations in 3 team fights, I hate this meta.
Bastion ulted and D.va was nowhere to be seen, R.I.P.
Pretty nice ults considering you're not pairing them with grav.
Okay, so both times you lost the point it was 'cause Bastion ulted and D.va was distracted or de-meched. Without communication there's not much you could have done about that. I dunno, maybe you could have gone a dive hero and tried to work with Winston and D.va a bit better. Maybe D.va could have swapped to Roadhog and saved hook for Bastion. Whatever, hindsight's 20/20. If you had any skill on Junkrat I would have swapped to him in that situation, but that's probably about all you could do alone.
Okay, so if you see a Sym on the enemy team and you go through a choke, always let Winston go through first.
Also, if your team isn't fully regrouped and ready to go, don't do poke damage. You're almost never gonna kill anything, and you'll just end up either dying, charging enemy support ults, or both.
Okay, so their Sym didn't do a completely idiotic sneak attack this time, and she closed off the flanking route with Junkrat. This is where Hanzo really starts to look bad. You didn't have a lot of options here. You walk into the left flank and Junkrat and Sym probably kill people if Winston doesn't go in first. You go down the middle or to the right and Bastion and Junk shred through everything before you get anywhere. The best thing your team could have done was swap the Zen to Lucio, and you go like, Genji or Tracer or something. This would be in a perfect world where everyone can play every hero well.
The best thing your team could have done without changing comp is Winston goes in and takes out the Sym turrets while D.va eats Junkrats bombs. Maybe you pick either the Junk or Sym off. Your team would then try to establish control of the high-ground and you just kill things from up there.
One thing you've always got to be looking out for is trickling your respawns. I noticed on overtime attack that pretty much your entire team after losing the first push, just didn't group up, and kept peeking out and getting destroyed by the Bastion and Junkrat. This was a massive waste of time and probably the best thing the defense could have hoped for. The correct play here was to tell everyone through text chat to wait behind a corner until the entire team was alive and ready to push.