Gaara is another candidate. His past as a feared and isolated shinobi could be the basis for a story where he is wrongly imprisoned again. His growth and his newfound understanding of friendship could be put to the test in prison, and he could also inspire other prisoners with his own story of redemption.
Naruto is a very likely character. Given his rebellious nature and his history of being an outcast in some ways, it's easy to imagine a scenario where he gets caught up in something that lands him in prison. His determination to break free and his loyalty to his friends would make for an interesting story.
Sasuke could also be a prominent character. His past actions of leaving the village could potentially lead to him being imprisoned in some fanfictions. His complex personality and his quest for power could be explored within the prison setting, like how he might use the time in prison to further his goals or come to some new realizations.
For Naruto side, Naruto himself is very likely. His determination and growth arc can be interestingly combined with DC elements. Also, Sasuke with his powerful Sharingan could have some cool interactions in the DC universe.
Iruka Sensei could also be a prominent character. He was an important figure in Naruto's early life. In a second - chance story, he might play a role in guiding Naruto in new ways, or perhaps Naruto could use his second chance to repay Iruka's kindness in a more significant manner.
Sasuke would be a likely character. He already has a dark past and a tendency towards brooding and seeking power, which would fit well in a 'world of darkness' setting. Orochimaru is another one. His experiments and his general amorality make him a natural for a darker Naruto story. And of course, Madara Uchiha. His grand and often cruel plans for the ninja world would be further explored in a darker fanfiction.
Sasuke would likely be featured. Since he and Naruto have a deep bond, Sasuke might be involved in Naruto's decision to retire or in filling the void left by him. Also, Naruto's family, like Hinata and his kids, would be important characters. They would be part of Naruto's post - retirement life, showing how they support him or how they are affected by his new lifestyle.
Naruto himself is very likely to be featured. He's the main character after all.
Well, for sure Yugi would be in it. He has that special bond with the spirit of the Millennium Puzzle, and that could lead to all sorts of adventures in the world of The Ocarina of Time. Then there's Joey. His loyalty to Yugi and his own dueling skills could play a role. In terms of The Ocarina of Time characters, Zelda would likely be involved. She has her own powers and knowledge, and her interaction with the Yu - Gi - Oh! characters, especially Yugi, could be really interesting. And of course, Ganon could be a major antagonist in the fanfiction, causing trouble for both sets of characters.
Some fanfictions might also feature the prison guards as main characters. They could be complex characters with their own motives and backstories, and their interactions with Naruto could drive the plot forward. For example, a guard who initially sees Naruto as just another prisoner but then comes to respect him.
In this fanfiction, Naruto will surely interact with his friends who might be trying to break him out or at least communicate with him from the outside. Inside the prison, he'll encounter inmates with diverse personalities. There could be a wise old prisoner who imparts some valuable wisdom to Naruto. Also, there may be a group of inmates who form a sort of gang within the prison, and Naruto has to either fight them or make peace with them depending on the situation. And of course, there could be a mysterious figure who seems to know more about Naruto's presence in the prison than he himself does, and Naruto will have to figure out this person's motives and identity.
For the Infamous side, Cole MacGrath would be a likely candidate. His powerful electrical abilities would make for an interesting dynamic in the Overwatch universe. On the Overwatch side, Tracer would be a great fit. Her speed and agility could contrast with Cole's more brute - force power. Also, Reinhardt could be involved. His chivalrous and protective nature would be interesting to see interacting with the Infamous characters.
Shepard from Mass Effect is a very likely character. Given their leadership skills and experience in dealing with various alien threats, they would be a natural fit in a crossover. They could potentially lead XCOM forces or at least be a key figure in coordinating between the two universes.