This is kinda for those who didn't get imprisoned by the elements. I like to honestly here how each of your got to where they are now.

Trevor Philips: came to Equestria as stone

Deathwing: was there at the planets creation and imprisoned inside the planet

Loki: Was the elements of Disharmony

Dox: Just showed up. Passed out after buying something from the merchant, then literally fell into Equestria.

Alex: Was harshly teleported by the Merchant and crashed into unknown area, but was summoned to his Discord's side shortly before said Disharmony God's petrification, due to him being a 'wonderful source of chaos', according to Discord.

Sam: Appeared in Twilight's library. Works hard to protect others. Lives in his ship. Not much in his life.

Spawn: Simply lived through the ages.

Black Alice: Unknown to her.

Pariah Dark: Is too strong for the Elements but was put to sleep partially (Not by the sisters) and eventually awoken.

Young Xehanort: Time.

Asura: Demi-God.

4289202
4289211
4289213
4289226

Is this it?

4289277
No, there's more out there.
I think there is.... I hope there is.

Wayde Molan: Went to bed in hotel, woke up in shadows that tried to eat him, subsequently was put to work as castle help to repay debt to society.

Jack the slasher: arrived as necromorph but was made more human by Luna's help and rose into the rank of leader of the Guard and works to protect Equestria. Lived for full thousand years and onward by simple biological immortality and force of will

4289301 there 350displaced

Does Shade count? He was blasted by the elements, but not turned to stone...

4289382
Yes there are. Most of them follow the stone thing. Some don't.

4289383 Well kinda but also no.

Mistress Change: Sealed with the crystal empire.
Duncan/Syaoran: Appeared when the crystal heart was recovered.

Blood Cleaver: Was born in a human version of Equestria, kills a Displaced and gets their powers.

Jack Frost: Fought the Merchant and got sent to Equestria, unseen by all for over 16000 years.

Malthael (Rise of the angel of death version) Though not apart of the whole thing (doesn't really want crossovers) he immune to harmonic blasts and been imprisoned in tartarus for thousand years. Fun fact I had a hand in the story.

Xellos: Showed up after Discord's first stoning, and ran whenever they tried to power up the Elements on him. Seriously what kind of idiot just stands there while someone charges up or chants a big spell?

4289448 Well some universes its locks on to the target or stops them in others it can be overpowerec but with a lot of magical force and others are kinda immune (Like Malthael (ROTAOD version))

Sombra: His arrival killed his Anthro counterpart, thus leading him down a darker path.

Doctor Doom: A sudden appearence in Maretropolis and currently trying to stay out of public view at this time.

4289180
Ryu: Switched himself with his [Aura] spell where said spell was turned to stone instead of him. He started training his magic after that.

Puppet Master, AKA Xander R. Herring, Transported to equestria, currently never been captured, though bound to be captured soon.

Nech and Lech: Twins who ate their elements of harmony and absorbed them over a thousand years as stone statues of their own choice, waiting for NM to return so that they could kick her in the butt and do what they want. Also appeared in Xander's fic, but yet to flesh them out in detail or have a character v character talk up. They went as those two owls from okami, whose names I'd speak of If I wasn't about to passout from sleepiness. Their nicknames should be clues enough to their cosplays.

Skargor Duffwort: The one messing with Xander, and also on the same world as another displaced whos name isn't revealed yet.

Wade Jallecks.
Wakes up looking at the side of the Apple family barn, immediately knocked out by apple family and tied up in barn.

Rock Light/ David/ Megamane.
Displaced by Discord, situated in Ponyvile under false identity enforced by townwide memory spell.

Richard Donahue/ Ryuko Matoi.
Wakes up right outside of Canterlot High stradling a motorcycle.

The Guardian
Fell out of the sky above a Dragon terrorizing ponies, eventually gets trapped in stone by a burst of combined Chaotic and Dark Magick for 1000 years

he was technically turned to stone, but not by Sunbutt

Freelancer, the character from my displaced in progress(chapter 1 is done and chapter 2 is in progress. I'm getting 3 chapters done before releasing it) was never imprisoned by Celestia in the first place. He just used a hidden ability in his item, the Asterisk to seal his own soul in there until the Crystal Empire reappeared... He got out a little early though.

Jason Hughes: Bought an Omnitrix and just appeared in the Everfree, later became a prince and married Chrysalis and Rarity

Domon Kasshu: Got a tattoo and arrived in equestria in the burning gundam and became leader of Equestria before giving sent to the shadow realm by Nightmare Moon.

Majin Buu: Helped a small village during an attack by raiders. Was later sealed away by a spiteful Bibidi.

4289277 well, most of Sam's adventures I haven't typed yet. But, Sam's biggest feats so far are that he stopped a Space Pirate invasion, killed ridley, and stopped and x invasion.

Eragon was involuntarily put in a stasis spell when Sombra pulled the Crystal Empire out of the timeline. The spell keeping him in suspended animation just lasted a couple years longer than what Sombra did to the Empire.

Illua: Was Dropped in, Found the corruption of nobility and destroyed it, only to be imprisoned in Stone by her own type of magic.

Robert: His friend bought him something from the Merchant and got pulled into a pool of darkness to Equestria, along with an unamed, unseen, other guy. Main goal is survival and escape ATM. No eternal imprisonment so far.

Lance: Passed out after purchasing something from the merchant to wake up in an abandoned Factory

Nuada (working on getting better at writing before posting first chapter) was placed in a cursed time locked room by Nightmare Moon, getting free when Elements purified her.

4289180 Jonathan Sanders/Yoshikage Kira: Got a tie from the Merchant and appeared in Canterlot during the Changeling invasion. The five displaced that appeared in that universe before him also count.

4289180 Heather/ Link: Sent to equestria by buying a magical crystal, woken up and nearly beat senselessly by RD.

Jake/Orpheus: Sent to equestria by buying a magical evoker gun. Awakened on beach by Dinky and now they have magical adventures! Sorta.

Adrian/Thanatos: Not disclosed yet but supposed to get there by buying a mask similar to thanatos' and woken in the everfree.

One of my ideas involved being stoned by celestia but I said no to it. It doesn't really work with my ideas.

Emerl: Sent to Equestria and became the vessal of Harmony while guarding her tree body and trained by her in a separate dimension meaning he is too strong to be imprision by Celestia. He is going to somehow rampage the moment he receives a large amount of discords energy, then Harmony will be force to banish him to that separate dimension or he'll be stopped by someone. Still in progress either banish or let a displace beat some sense into him.

4289180 Celedon befriended the Princesses after crashing into the throne room and explaining her position. Then again, but Celly and Luna are much more mature and realistic, I think. She was no threat to the nation, thus no stoning. Now Berserker on the other hand...