She does too much. She’s a mini tank/healer/dmg.
Tank
She has a mini shield like reinhardt and can block projectiles for her team members. She also has a lot of health and can further increase her health with her ult. In close range, she’s impossible to beat because she can block projectiles with mouse2, has two different stuns on 2 different cooldowns, and does a lot of damage with her mouse1.
Damage
She has two different stuns, shield bash and her shift. Her shift has a crazy long range, especially on tight KOTH maps like Busan. She can brainlessly mouse1 and rip apart squishies and supports to shreads. Literally, on some maps I’ve seen 2 first time Brigettes go on to get a player portrait and something like 60%+ kill participation. It’s not rare for her to be up there in damage output either.
Support
She throws a shield to allies that heals them and adds a shield if they’re full health. If they’re part health, the shield heals them up to full and the rest is used as a shield. This has a relatively low cooldown. As I mentioned already above, she also has a shield she can use to block projectiles for her teammates.
This is why people hate to play against Brig.