There are three ways to counter Orisa: destroy the shield quickly with burst damage, flank her with mobile heroes, or push through her with a dive or tank lineup.
Genji, Hanzo, Moira, Junkrat, Reaper, Tracer
Destroy Protective Barrier
Most hitscan and sniper heroes are countered by Protective Barrier because it blocks all their shots. This ability has a relatively low cooldown of 8 seconds and a duration of 20, so you need to destroy it very quickly before Orisa is able to deploy a new one.
Junkrat and Reaper are among the best choices because both the Frag Launcher and the Hellfire Shotguns can dish out a massive amount of damage, and Orisa’s barrier doesn’t have a lot of health (900). As a comparison, Reinhardt’s Barrier Field (which is also countered by the same heroes) has 2,000 health.
Reaper is particularly strong against Orisa due to her huge body and head hitbox. He can avoid the shield using Shadow Step and Wraith Form, and then annihilate her with a few well-placed shots. Orisa’s Fortify partially counters this approach granting her a 50% damage reduction, but at a close range Reaper can just headshot her with his shotguns.
Torbjorn’s turret is basically useless against her barrier.
Ignore the shield
Protective Barrier is both a strength and a weakness because Orisa and her team tend to play around it.
There are a few abilities that go through shields, such as Hanzo’s Dragonstrike and Moira’s orbs. These are extremely efficient because they can either kill a few opponents or force them to leave their placements, giving your team a numerical or positional advantage.
Flankers like Genji and Tracer can just go past the shield and attack her huge body. Due to Orisa’s big head hitbox, even a Tracer player with a terrible aim will be able to headshot her while moving without much effort.
A dive composition (D.Va and Winston) can just jump past the shield, ignore Orisa, and kill the squishy members of the team. This approach will cause chaos in the enemy lines, and most probably Orisa won’t receive sufficient help to hold the position.
Snipers. Some players believe that snipers are great versus her because they can easily hit her head, but an experienced Orisa won’t expose her weak point unless forced to.
The shield is stationary. Attacking her from multiple directions is also a solid tactic because she can’t just relocate the shield instantly as Reinhardt. Orisa mostly excels at defending one side at a time.
Deathball. Tank heroes can just rush through the shield, especially if speed boosted by Lucio. A typical example which dominated the meta is the GOATS composition. The success of this approach depends also on the heroes and coordination of the enemy team.
Related: All the Overwatch team compositions
Orisa versus Doomfist
Generally, Doomfist is countered with teamwork, and Orisa is one of the best picks against him.
She is immune to all his crowd control abilities thanks to Fortify as it prevents all forms of knockback.
Halt! precludes him from disengaging in the great majority of the battles, and a Doomfist stuck among your teammates won’t survive for a long time. Keep track of his cooldowns!
Countering the Orisa + Bastion combo
In a limited number of maps (Junkertown is the best example), the Orisa + Bastion combo on the payload is extraordinarily powerful and hard to deal with for most players.
Sombra is one of the best counters as she can easily sneak behind their defenses, hack Bastion, and in the best scenario also kill him. This is harder to pull out if the opponents have a certain degree of coordination, such as a dedicated healer for Bastion and Orisa, and an anti-flanker like McCree protecting the area around the payload.
A capable Tracer could also build her ultimate charge and then release the Pulse Bomb on Bastion, forcing the opponents to spread out, and potentially even scoring several kills.
If they are running a proper team composition such as the “Pirate Ship”, mirroring it (utilizing the same heroes and tactic) is often the easier way to defeat them. The team who breaks the opponents’ shield first will have the upper hand. As the defenders, I suggest a partial mirror: replace one of the heroes with a DPS able to destroy Protective Barrier quickly, such as Junkrat.
All the images and hero icons: Blizzard