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human
[MCU] What's it like in the timeline where Thanos, Gamora, Nebula and army just suddenly vanished in 2014?

They travel from that timeline's 2014, prior to Quill meeting Gamora,

Does Quill form the GOTG without Gamora? Ronan still wants the power stone for himself so many of the events of that movie happen, but without Gamora does he win? What is the knock-on effect?
gpt
We can only speculate.

Event of GotG:

Quill wakes up with the Orb on hand, but far after the OT (original timeline).  
So Korath and his men are already here.   
I suppose the fight would be nearly the same as the OT, and Quill would flee in the Milano and try to sell it on Xandar.

Without Gamora, Quill only has to fight Groot and Rocket, but he's as underpowered as the OT. The 3 of them are detained in the Kyln.

There, they wouldn't meet Drax, who meets Gamora because of Thanos, Ronan, blablabla.  
Rocket's plan of evasion would still work, because Quill would fill Gamora's role, and the 3 of them would evade.

But, instead of going to Taneleer Tivan (Gamora's idea), they would have another plan.

I don't really know what will happen after that, but either Ronan find and kill them, or they are killed during the battle of Xandar, because Quill is foolish and stubborn and won't survive without his ninja girlfriend, or they will disband and mind their own business.

Aftermath of Gardians of the Galaxy

* Xandar is destroyed and Ronan possess the Power Stone.
* The Gardians never really assemble, and are either dead or don't care about other than themselves.

GotG 2:

If Quill is dead or absent from the Battle of Xandar, Ego will never hear of him.  
He won't search him, he won't try to conquer the universe... for now.

Event of Infinity War:

* Thanos never attack the Statesman (Thor's ship)
* Thor will land to Earth and establish New Asgard in Norway.

Variables:

* Ronan has the Power Stone. He might want to seek revenge on Captain Marvel.
* Taneleer Tivan still has the Reality Stone. He might want to collect the other 5.
* Vision keeps the Mind Stone.
* Loki keeps the Space Stone, without Thor knowing.
* Dr Strange keeps the Time Stone.
* The Soul Stone is still on Vormir, without anyone knowing.