It hit me not long ago that Zefram Cochrane was still alive in First Contact's timeframe. and some research showed at least one soft canon example of this
We have at least an idea of most of the TNG crew's whereabouts. Riker was last seen commanding the Titan alongside Troi. Geordi commands the Challenger and is on his second wife. Data commands the Enterprise. Picard is retired on earth after a lengthy stint as Vulcan ambassador and has a son running a Martian Vineyard. I think Beverly Crusher is possibly commanding the Pasteur. Wesley remains something of a mystery but my unsubstantiated pet theory I'm partial to is that he's still with the Traveler and the time we saw him in Nemesis was the first Undine infiltrator.
There's less generally known about DS9 and Voyager's crews aside from Janeway, The Doctor, Seven, Kira, and Sisko.
But there are potentially some TOS and TOS-era stragglers out there.
One of those is M'Ress. Cryptic might not have access to her via the cartoons or comics but she was in the TNG era novels, which Cryptic seems to have some liberties with.
I think most sources have Admiral McCoy as dead. Kirk is dead in most takes. Spock is in another universe.
However, what sources there are seem to suggest Scotty being alive (and active) even after STO's timeframe
Morgan Bateson (a TNG character from the TOS movie era, played by Kelsey Grammer, who as a fan seems to be quite liberal with allowing his likeness to be used in follow-up appearances) seems likely to be active.
You have Trill, like Dax. (Is she still Ezri?)
It's unclear how old Cardassians live to be or if people like Dukat and Garak were contemporaries of Kirk, although I've noticed most fans seem amenable to Dukat at least being a veteran of the TOS era , at least as a young grunt, given that he looked the same when Kira was born as he did in DS9 and had a lengthy career that included some major demotions.
Just curious who was alive in the TOS era that's around today.