While the final battle in former SHIELD director Nick Fury was noticeably absent in the war against Thanos. While Endgame's writers gave logical reasons as to why Samuel L. Jackson's character was left out, there's still a way the master spy could have been a major player against the Mad Titan.
As seen in the post-credits scene for Avengers: Infinity War, Fury, and his second-in-command Maria Hill were both dusted when Thanos snapped his fingers, being part of the half of all life that was erased in what would come to be known as the Decimation. As such, neither would be seen until after the Avengers retrieved the Infinity Stones from the past to bring back those they had lost. While this resulted in many of the erased Avengers returning just in time to take on Thanos and his armies, Fury and Hill were not present. According to co-screenwriter Christopher Markus, it was determined that Nick Fury wasn't in Endgame's final battle because he "would just be firing a gun" amid multiple heroes wielding all kinds of incredible powers. However, it should be evident that Fury could have brought something huge to the table.
As seen in the original Avengers, Nick Fury offered Earth's Mightiest Heroes plenty of air via the impressive SHIELD helicarrier. Despite SHIELD's end seen in Avengers: Age of Ultron. Bringing in the impressive aircraft to Endgame's final battle would have been poetic, continuing an Avengers trend while having Fury provide some epic firepower to the heroes he helped assemble (going way beyond a simple pistol).
How Endgame Could Have Used Fury & The SHIELD Helicarrier
The helicarrier could have easily justified Fury's presence in the final battle against Thanos, especially seeing how the Mad Titan has his own ship overhead known as the Sanctuary II. However, the helicarrier could have done even more. While Endgame saw Carol Danvers' Captain Marvel arriving to destroy Thanos' warship during the final battle, Fury and the helicarrier could have been right behind her. Seeing as Danvers was largely still a newcomer to heroes and fans alike at this point in the MCU, Fury could have shared her debut, giving her a smoother introduction as someone she actually knew. Working in tandem, they could have taken out the Sanctuary II before offering to the Avengers below.
The final battle of Avengers: Endgame is rightly seen as the all-encoming culminating conflict to conclude the MCU's Infinity Saga. However, Nick Fury's absence is what keeps the battle from total perfection, the difference between an "A" and an "A+." To that end, using the SHIELD helicarrier seems like it would have been the perfect way for Nick Fury to enter the fray, rather than the former SHIELD director only showing up in the aftermath for Iron Man's funeral.
