Overwatch game director Jeff Kaplan said Overwatch Patch 1.30 will include buffs for Mercy, Roadhog, Symmetra, and Reaper, in a developer update released Monday.
Kaplan didn't go into much detail about what the changes would be, but he did mention that Mercy will strictly be getting a buff to Valkyrie.
"Mercy will be getting a buff specifically to Valkyrie that we're experimenting with that should be pretty awesome for her and a welcomed change," Kaplan said.
Roadhog will have many changes to his hook properties and shotgun consistency. Roadhog has been consistently plagued with bugs surrounding his hook, and inconsistency with his shotgun. A fix for both of those problems would bring him into relevance in the current Overwatch meta. The changes to Mercy will likely not be very extreme because Blizzard is very conscious of how little power she needs to receive to become overpowered.