Besides reaper?
Maybe McCree?
Honestly the best answer is Roadhog. Winston doesn’t pose a threat, shotguns melt him, he can tug him back or to peel, and his ult can easily counter Winston’s. As far as DPS Hanzo can hold him back, Sombra can remove his much-needed movility, Mei can freeze him in place, etc. Really any non-dive DPS can.
Tracer and more Tracer.
McRightclick, Torb, or Bastion
High burst/damage DPS I believe, as well as cc. Like people have said McRightclick is probably the best as of right now, maybe Ashe because she can blast him away and unload her gun into him? But I’m probably wrong on that one
hard counter: tracer, sombra, reaper, mcree (depends if your smart), pharah (good monkey can contest pharah to an extend)
if u can click heads these heroes have the potential to become soft counters if not its most likely an even match up: widow, ashe, hanzo, soldier (Not so much but he’s healing station can give im the edge)