Overwatch's myriad balance changes will continue soon with a bunch of tweaks to the shooter's support heroes. Ana, Brigitte, Lucio, Mercy, and Moira will all be changed in the next PC PTR update, developer Blizzard has stated.
The biggest change sees Brigitte's Shield Bash cooldown increasing from six seconds to seven seconds, as Blizzard wants to allow more counter-play against her--her win rate is the highest of any support hero right now.
Going forward, Ana's Nano Boost heal its target by 300 HP instantly, in addition to its existing powers. Blizzard says the new Nano Boost will allow Ana "to use her ultimate as a clutch save on a dying teammate, or even use it in combination with her Biotic Grenade for a huge instant heal on even the biggest of tank health pools."
Lucio's changes, meanwhile, pertain to his Sound Barrier and Crossfade abilities. The former's effect is getting increased from 500 to 750 shields, while the latter's aura radius will also be going up, from 10m to 12m, so the hero can have "more flexibility in how he moves while still maintaining his powerful support songs to help out his team."
Mercy is getting nerfed once again. Blizzard is reducing her primary fire healing power from 60 HP per second to 50 HP per second, as the company feels other healing characters struggle "to compete with her for a spot on a team" thanks to her high rate of healing over the course of a match.
Finally, Moira is getting a relatively minor change--her healing resource regeneration rate is going up by 20%--while Zenyatta will remain the same as Blizzard feels "he is in a pretty good spot." For more on the changes, check out the developer notes on Blizzard's forums.
In addition to the above changes, Overwatch has a brand-new hero coming soon. Named Hammond, the character is a hamster whose in-game code name is Wrecking Ball, and he's launching on July 24. It's unlikely the above changes will go live simultaneously with Wrecking Ball's release--Blizzard merely states those tweaks "are coming to the PTR very soon."