One possible fanfiction could be where Orochimaru somehow gets involved in the Teen Titans' world and meets Red X. Maybe Orochimaru is after some sort of powerful artifact that the Teen Titans are protecting. Red X, being the mysterious anti - hero, might initially see Orochimaru as a potential ally to get his hands on the artifact for his own gain. But as the story progresses, he realizes Orochimaru's true evil nature and teams up with the Teen Titans to stop him.
Perhaps Danny is from a parallel dimension and has been searching for a way to get home. He crosses paths with the Teen Titans and Red X. They initially think he's a threat but soon realize he can be of great help. He starts to share his knowledge of different dimensions which could be useful in their fight against villains.
It could start with a strange energy rift that connects the Naruto and Teen Titans universes. Orochimaru, always seeking new powers and knowledge, senses this and decides to investigate. Red X, on the other hand, is in the middle of a heist in the Teen Titans' city when he is suddenly pulled into the rift along with Orochimaru. Naruto, who is training nearby in his own world, also gets caught up in the energy and is transported to the Teen Titans' world, setting the stage for their interactions.
One interesting plot could be about a common enemy that forces Naruto, the Justice League and the Teen Titans to team up. They have to overcome their differences in fighting styles and values to defeat this powerful foe. Another plot might be a competition between the three groups to see who can solve a mystery or complete a mission first, which would lead to a lot of rivalries and interesting interactions.
Well, at first, the Titans would be very suspicious. Robin has taken on the guise of a former enemy. They would keep their distance and watch his every move. But as time goes on, if Robin uses the Red X powers for good, they might start to see that he's still the same person deep down. However, there would always be a bit of uneasiness, like they're waiting for him to snap and turn back into a villain - like Red X.
In a Naruto x Justice League vs Teen Titans fanfiction battle, Naruto could potentially hold his own against the Justice League. His shadow clone jutsu could confuse Superman for a moment, and his rasengan might be able to do some damage. But the Justice League has Batman's strategic mind. The Teen Titans, on the other hand, have Raven's magic and Beast Boy's shape - shifting. It would be a chaotic and exciting battle where the outcome would be determined by who uses their abilities more effectively at the right time.
You can try searching on fanfiction platforms like Archive of Our Own (AO3). It has a large collection of fanfictions for various fandoms, including Red vs Blue. Just use the search bar and type in 'Red vs Blue Church x Carolina' and it should show relevant stories.
One great 'Red vs Blue Carolina x OC' fanfiction is 'The Unlikely Alliance'. It has a well - developed OC who teams up with Carolina in an exciting adventure. The story really delves into their relationship development and the action scenes are engaging.
One plot idea could be that Danny somehow gets transported into the Teen Titans' universe. He teams up with Red X, who is initially distrustful but they gradually form an alliance. They could be on a mission to stop a new super - villain that neither the Titans nor Danny has faced before.