In 'neji meets his alternat self fanfiction', one possibility is that they start to fight at first due to confusion and a sense of threat. However, as they get to know each other, they realize that they have more in common than they thought. They could end up learning from each other, like sharing different jutsu techniques or ways of thinking about their ninja duties.
Perhaps Neji's own insecurities could be the main antagonist in a sense. When he meets his alternate self, he might start to feel inadequate or question his own identity. This internal struggle could be the main obstacle they have to overcome rather than an external enemy.
In such a fanfiction, Neji might initially be in shock when he meets his alternate self. He could start to question his own life choices and beliefs. For example, if his alternate self has made different decisions regarding his loyalty to the clan or his relationships with other characters, it would force the original Neji to re - evaluate his own stance. Maybe they would even engage in a sparring match to test each other's skills, which could lead to a new understanding of his own abilities.
Maybe a dark version of Neji himself could be the antagonist. This could be a Neji from a parallel world where he succumbed to hatred and envy. He might try to destroy the 'good' Neji and take over his life, believing that his way is the right way and that the other Neji is a weak version.
Perhaps in this fanfiction, Neji is brought back to life somehow. Boruto, being curious, approaches Neji. Neji then discovers how much the ninja world has changed since his time. Boruto could show Neji the new technology in the Hidden Leaf Village. Neji might be a bit shocked at first but then start to see the potential in these new things. They could also form an unlikely friendship, with Neji guiding Boruto in matters of honor and discipline, which are values Neji held dear.
One interesting plot could be that Boruto accidentally travels back in time and meets Neji. At first, Neji is on guard, thinking Boruto is an enemy. But when Boruto explains his situation, Neji decides to help him get back to his own time. Along the way, they face some common enemies. Boruto shows Neji some of his unique abilities, and Neji teaches Boruto some of his wisdom and combat skills.
In this fanfiction, Percy might be shocked at first to see his younger self. He could offer advice to his younger version, like how to better handle the challenges in the magical world. Maybe he'd warn his younger self about certain enemies or mistakes he made in the past.
In this 'Naruto meets his female self' fanfiction scenario, it could be that his female self has a different personality. She might be more in touch with her emotions. They could initially clash because Naruto is used to his own way of doing things. But then they might learn from each other. For example, Naruto could learn how to better handle his relationships from his female self, while she could learn his fearless attitude in battle.
In this kind of fanfiction, Natsu might have some really interesting interactions. He could try to warn his past self about future challenges or mistakes. For example, he might tell his younger self about a particularly difficult battle and how to better prepare for it.
In this fanfiction, Steven could learn valuable lessons from his future self. For example, he might find out how to better use his powers or how to handle difficult situations with the Crystal Gems. Maybe his future self would warn him about upcoming threats and how to avoid them.