Well, obviously the two main characters are Batman from the normal DC universe and Flashpoint Batman. Batman is the well - known Dark Knight, a symbol of justice in Gotham. Flashpoint Batman is from an alternate timeline, with different experiences and a potentially different personality.
Another idea might be that one Batman is from the future and has come back to meet his past self. The future Batman could show the past version some new technologies and tactics, but also warn him about the potential consequences of certain actions. This could lead to self - reflection for the past Batman and a change in his approach to crime - fighting.
Sasuke would likely be aloof and guarded at first. He might see Batman as just another 'vigilante' like some of the shinobi in his world. Batman, on the other hand, would be cautious and try to figure out Sasuke's motives. Eventually, they could start sharing their combat techniques. Sasuke might show Batman how to use chakra in combat, and Batman could teach Sasuke about the importance of having a strong moral code.
One possible scenario in this fanfiction could be that Tim Drake initially looks up to Batman from afar. He might be in awe when he finally meets him, perhaps during a crime - fighting situation. Tim could be trying to prove himself to Batman, showing off his detective skills that he has honed over time.
Another plot development could be that Flashpoint Batman tries to convince the regular Batman to change his ways. He might see the regular Batman's methods as too soft or ineffective. This could create a lot of internal conflict for the regular Batman as he questions his own beliefs and methods in the face of this alternate - self's criticism.
Perhaps they could start off as rivals in the fanfiction. Batman from the present is skeptical of Batman Beyond's more high - tech approach. But as the story progresses, they learn from each other and become a great team. For example, Batman could teach Batman Beyond some of his old - school detective skills, while Batman Beyond shows Batman new ways to use technology in combat and surveillance.
Robin could be a great addition. He could act as a bridge between Starfire's more light - hearted nature and Batman's seriousness. His acrobatic skills and detective training could complement both of them in a fight. Another good character would be Nightwing. He has a connection to Batman already and his charm could add an interesting element when interacting with Starfire.
It's really hard to say. Batman has a vast array of high - tech gadgets and is a master of martial arts. But Daredevil has his super - enhanced senses which give him an edge in combat. If it's a straight - up fight in a dark alley, Daredevil might be able to use his senses to anticipate Batman's moves. However, Batman is very strategic and could potentially use his gadgets to disorient Daredevil. So it could go either way depending on the circumstances.
A new tech - savvy villain who is a master of hacking could be introduced. This villain could pose a threat to both Batmen as they rely on technology in different ways.
In a 'batmankoff meets batman fanfiction', perhaps there could be an epic battle. Batmankoff might initially be seen as a threat by Batman. They could engage in a physical fight across the rooftops of Gotham. Batman would use his combat skills and gadgets, while Batmankoff could have some unique abilities of his own that Batman has to figure out.