What if Captain America was never found? Or if the alien in its last seconds of life killed Hank Pym before he and Janet Van Dyne could become Ant-Man and the Wasp.
What would happen if the All New all Different X-men and the originals died on that island? Or if Thor never enraged his father and was exiled to Earth or if Tony Stark didnt survive the mine blast that mortally wounded his heart?
What if Bruce Banner didnt survive the Gamma Bomb and the only one of the four astronauts survived that the cosmic rays?
Would the Avengers be created?
In short yes. With the backing of Janet Van Dyne and Thomas Fireheart AKA The Puma a group of super powered individuals were created to fight menaces too powerful for any one person or nation to deal with. The group consists of the mystic defender Dane Whiteman The Black Knight wielder of the Ebony Sword and Shield of Light, the mutant cat burglar extraordinaire, Kitty Pryde, Shadowcat. The Kree ambassador Carol Danvers, Captain Marvel. The survivor of the space launch Reed Richards now known as the Thing and his assistant Roger Boches pilot of the Box armor. And last Richard Rider now known as Comet Man fight all types of evil to protect the world and its innocents.