Any character with strong early-life ties to Starfleet could be endangered, even the half-human Troi, who was fathered by a Starfleet officer. The farther out you get from Earth, Starfleet, and even Federation origins in general, the likelier the chances for survival.
General Worf is likely already alive during Trek '09's era, so assuming he wasn't on any of those 47 doomed Klingon ships, then the Worf we know could be very much alive later on. Who knows if he'd live the same life, though.
Data could very well exist. Arik Soong's switch from biology to cybernetics has already happened in this timeline, so unless that development got sidetracked somehow or Noonien wasn't born for whatever reason, then all
the Soong-type androids could be out there.
Guinan is almost certainly alive and well. Soran, too. That whole El-Aurian refugee situation would still happen as it's way
far afield of the timeline changes centering around the Federation.
Tasha Yar could be alive. Her colony was independent, wasn't it? I can't recall... not enough of its history was really firmly established, other than it being a hellhole. Who knows? Maybe she stands a better chance in this timeline than the Prime one.
Most Delta and Gamma Quadrant characters would be unaffected, with the possible exception of Seven of Nine. A lot of DS9's characters would probably be okay, actually; certainly all the Cardassians and Bajorans at least. Speaking of which, this era's Dax is probably doing fine too, but who knows if the line of hosts would stay the same going forward.
Unfortunately, any and all non-Spock Vulcans are probably screwed. Tuvok, Tuvix
, the baseball Vulcans, Torres' gopher... all of them.