Overwatch players are testing a number of heroes as counter for Sombra. Fortunately, testers were able to find at least four of them who can resist her hacking charms.
Symmetra Versus Sombra
Symmetra is turning out to be a decent counter for Sombra, according to Pvplive. Her microwave turrets can be perfect trap for Sombra since she can't hack them.
Winston Versus Sombra
Winston's barrier is vulnerable to Sombra's electromagnetic pulse (EMP) charge. However, this does not mean he is entirely defenseless. There is no way that Sombra could disable his high jumps. His electric barrage has a wide range of fire that can forced Sombra out of her invisible mode.
Junkrat Versus Sombra
Sombra's cloaking ability enables her to sneak on the enemy. Fortunately, Junkrat can negate this ability by laying out mines. Once Sombra unwittingly steps on one of the mines, her cloak is disrupted which will allow Junkrat or his allies to take her down.
Soldier 76 Versus Sombra
Sombra' EMP has little effect on Soldier 76 and also has his own biotic emitter in case the health packs have been hacked, according to the official Overwatch site. Soldier 76 may be unable to track Sombra with his Tactical Visor, but he could force her out and damaged her with his Helix Rocket.
Other Potential Counter For Sombra
Bastion has always been teased as a pushover against Sombra's hacking prowess. However, she has to sneak behind the walking turret first. Other heroes such as Mcree, Pharah and Reaper are also being proposed but many are not convinced by their effectiveness against Sombra based on the discussions on the Overwatch forums.
Conclusion
Ultimately, countering Sombra by any hero in Overwatch will depend on the skills of the player. The female hacker is dangerous one if used by an expert player but an annoyance if controlled by a novice or one who is not familiar about her abilities.
