For Naruto, his shadow clone jutsu could be combined with a Stand's ability. Imagine his clones also having the power of a Stand. So, if he has a Stand like Star Platinum, all his clones could use Star Platinum's super strength and speed. In the case of Jojo characters, someone like Josuke Higashikata could use his Crazy Diamond to repair ninja tools or even heal ninja injuries. His ability to fix things could be really useful in the Naruto world where battles often lead to broken equipment and injured comrades.
A cool plot could be a time - travel story. What if Jotaro Kujo somehow ended up in the Naruto universe? He could use his Star Platinum to take on some of the powerful ninja there. Or perhaps Naruto travels to the Jojo universe and has to learn how to use Stands. He might befriend some of the Jojo characters and together they face off against the enemies in that world. Maybe Dio Brando discovers the power of chakra and tries to use it to enhance his vampire abilities, which would draw the attention of the Naruto characters who would then try to stop him.
Another characteristic is creative plotlines. In a Jojo x 'Fullmetal Alchemist' crossover, the story could revolve around the search for the Philosopher's Stone in the context of Jojo's world, with the Homunculi having an interest in stands. This kind of unique plot keeps readers engaged as it combines the best elements of both franchises in unexpected ways. Also, good fanfiction in this genre usually has great dialogue that reflects the distinct voices of each character from the different universes.
Definitely Jotaro Kujo. His cool and stoic personality, along with his powerful Star Platinum stand, makes him a favorite for crossovers. He can easily be inserted into different universes and hold his own against various opponents.
In some 'jojo crossover fanfiction', there could be a crossover with a historical setting. Like having Jonathan Joestar in ancient Rome. His gentlemanly ways and hamon powers would be quite out of place yet fascinating in that context. He could interact with Roman gladiators and senators, changing the course of history in this fictional scenario.
One great 'Jojo Crossover Fanfiction' is 'Jojo's Bizarre Adventure x Persona'. It combines the unique stand abilities from Jojo with the Persona summoning mechanics. The story often has the Jojo characters interacting with the Persona characters in a very interesting way, like Josuke Higashikata teaming up with a Persona user to fight a common enemy that has elements of both universes.
How about a story where the Avengers are pitted against Dio? The Avengers would have to deal with Dio's time - stopping ability with their own powers. Iron Man could try to create a device to counteract Dio's time stop, while Captain America uses his strategic skills to lead the fight against Dio's minions.
One idea could be a crossover between 'Jojo' and 'Harry Potter'. Imagine Jotaro in Hogwarts, using Star Platinum to perform magic in a unique way. Another could be a 'Jojo' and 'My Hero Academia' crossover, where the stands of 'Jojo' characters interact with the quirks of 'My Hero Academia' characters. Or perhaps a 'Jojo' and 'Lord of the Rings' crossover, with Jojo characters on a quest in Middle - earth.
A great concept for a 'jojo persona crossover fanfiction' would be a tournament - style story. Characters from both universes are forced to participate in a battle royale. The Jojo characters would bring their Stands, and the Persona characters would have their Personas. The battles could be intense, with different strategies emerging. For instance, a Persona user might try to use psychological attacks against a Jojo character who is more used to physical combat with their Stand. And the story could also explore how the two groups of characters interact and form alliances outside of the battles.
One common theme is power exploration. Writers often explore how the stands from Golden Wind interact with powers from other universes. Another theme is friendship. They show how characters from different backgrounds form new bonds.