What could be the possible plot in 'black swordsman vs vecta fanfiction'?

It's hard to say. The Black Swordsman has his sword skills, but Vecta could have some unknown powers. If the Black Swordsman's sword can cut through any defense, he might be more powerful. However, if Vecta has the ability to control minds or something like that, he could turn the tables.

Well, one possibility could be that Sonic and Eggman are forced to team up against Black Doom. Maybe Black Doom is threatening to destroy their world, and they realize that only by combining their strengths, Sonic's speed and Eggman's technology, can they stand a chance.

One possible storyline could be that Naruto is somehow transported to Goku Black's universe. There, he has to face Goku Black who sees him as an intruder. Naruto would have to quickly learn about Goku Black's powers and find a way to fight back using his ninja skills. Another storyline could be that a powerful villain creates a rift between their two universes and pits them against each other. They start off as enemies but then realize they are being manipulated and team up to fight the real villain.

There could be a storyline where Beerus, out of boredom, decides to train Goku Black instead of fighting him. But Goku Black misinterprets this as a sign of weakness and attacks Beerus. This could lead to a battle where Beerus has to hold back at first to avoid killing Goku Black, but as the fight progresses, he realizes he has to use his full power to subdue him.

One interesting plot point could be the initial encounter between the two. How would they react to each other? The Black Swordsman might be cautious seeing such a powerful being as Dark God Vegeta. Another point could be the discovery of each other's weaknesses. Maybe the Black Swordsman finds a way to temporarily nullify Vegeta's energy attacks, or Vegeta discovers that the swordsman's sword has a special power that can harm him. Also, the moment when they start to respect each other's fighting abilities during the battle would be really engaging.

One possible plot twist could be that Jiren discovers a way to nullify Saitama's strength. Maybe he finds some sort of energy - draining technique that weakens Saitama over time. Another could be that Saitama holds back for some reason, like he wants to see the full extent of Jiren's power, and in doing so, he gets into a real struggle.

Another plot twist might be that Luffy actually loses the first round of the fight but then finds an inner strength or a new power - up from an unexpected source, like a memory of Roger or a new Devil Fruit ability that he unlocks in a moment of desperation.

One possible storyline could be that Goku Black arrives on Earth in search of a powerful energy source. The Justice League detects his arrival and confronts him. At first, they underestimate his power. Goku Black easily defeats some of the members, but then the League starts to work together and figure out his weaknesses. Another storyline could be that an evil entity has brought Goku Black to the DC Universe to cause chaos and the Justice League has to stop him while also dealing with the entity. Or perhaps Goku Black is tricked into thinking the Justice League are enemies of the Saiyans and he attacks them, only to later find out the truth and have to team up with them to fight a greater threat.

A plot development could be that Gaara and Sasuke start the fight. Sasuke tries to taunt Gaara about his past and how he could never truly understand Sakura like he does. Gaara, in response, shows his determination through his sand attacks. As the fight progresses, Sakura starts to see a side of Gaara she never knew, which makes her question her feelings for Sasuke. Meanwhile, Sasuke becomes more and more frustrated as he realizes he might be losing Sakura's attention, which makes him fight even more recklessly.

In this fanfiction, it could be about a philosophical difference. Lily Potter might have a different view on how to deal with the threat of Voldemort. Dumbledore is often very strategic and calculating, while Lily could be more impulsive and driven by her emotions and motherly love. So, they could be at odds over how to train Harry or which allies to trust in the fight against the Dark Lord.