One thing I can guarantee is that Mercy will be nerfed. The only part of her kit that would stay the same is probably resurrect. But, because now that its 5v5, in order to rez, Mercy has to leave the team in a 3v5 for 1.75 seconds and then a 4v5 for 2.25 seconds until the person is actually back.
Assuming Mercy isn’t killed or stunned, resurrect got an indirect nerf.
The saddest part is that I can also guarantee that resurrect will feel just as bad to use as it currently is where you die to go for a rez in the middle of combat (which is objectively the only time it can make an impact, doing one after or before doesn’t change the outcome of a fight the way a mid-fight rez can tip the scales), get killed right after the rez, get the person killed again because its not exactly inconspicuous, or get killed after and the person killed again, effectively feeding a triple kill from just one death that would’ve only been one death had Mercy literally done nothing.
They want to keep it with Mercy except that resurrect is not a core part of her gameplay. It comes up less often than her ultimate and is often risky as is. Its very feast or famine but often its better to have a hero that can prevent the death to begin with.
Objectively speaking, resurrect requires failure in order to use and has no use case beyond that. When she was reworked, resurrect was part of her core game-play but to the extreme. The nerfs were warranted but led to resurrect not being a core part of her gameplay. Its not an ability you can rely on nor is it a reason to pick Mercy due to its situational and unreliable nature.
It will never happen now, but I think if when they did the last batch of nerfs to Mercy instead of giving her the cast time but leaving in the double rez from Valkyrie, they had just removed the resurrect reset and charge in Valkyrie Mercy could have had resurrect without the cast time or slow-down. After all a single use every 30 seconds is more than balanced.
The problem came with the way resurrect interacted with Valkyrie to give it more charges or reset the cooldown.
Its why even with the cast time, it did little to change her dominant status. Had they instead just removed the interaction with Valkyrie and left resurrect as a static 30 second cooldown like every other normal ability (besides swift strike) that cannot have its cooldown refreshed or reset it wouldve been a different story.
That said, Mercy is in a good spot right now and even becomes meta every now and then so I doubt this change will ever happen.
In my personal opinion I wish they would just remove resurrect altogether and replace it with something like Divine Palm which is an ultimate ability the character Kharazim has in Heroes of the Storm, or swap valkyrie and resurrect (with a nerfed valkyrie of course) and just have a single instant resurrect as her ultimate, no charges, just a resurrect. Have it charge somewhat faster like Tracer’s pulse bomb or leave it as is. Seeing as how you can charge Valkyrie up currently in faster than 30 seconds.
I’ll reiterate to say I don’t anticipate any of these chnges coming as Mercy is in a fine spot and doesnt need any changes, this is just my personal opinion and what I would like to see, as I do not think resurrect is a core part of Mercy’s gameplay as it is and would like to see that become the case or have it scrapped (which I can pretty much guarantee will never happen but I can hope).
TL;DR
I can guarantee 2 things:
Mercy will be nerfed in some capacity
Resurrect will stay the same, and feel just as bad to use as it currently does (I don’t find it fun to use as it cannot even be cancelled and is essentially a self-stun. You can argue its fun to go for a risky rez, but as I mentioned its way too situational and unreliable to do so)
And the rest was just some hopeful thinking/ dreaming.