A fanfiction could focus on a friendly rivalry between Ryu and Sakura. They might compete in local street fighter tournaments. Sakura is always eager to prove herself against the more experienced Ryu. And in the process, they both learn respect for each other's fighting styles.
Luffy from 'One Piece' could also be an interesting crossover. Luffy's stretchy abilities combined with Ryu's martial arts would make for some unique fight scenes. They could also learn from each other's determination and loyalty to their friends.
They could team up to face a common enemy. For example, a new villain emerges in the Street Fighter world. Ryu and Sakura decide to join forces. Ryu's powerful hadokens and Sakura's energetic punches combine to create a formidable fighting duo.
One possible crossover could be Mr Bison somehow getting transported to the Fairy Tail world. He might try to take over the magic guilds using his Psycho Power. The Fairy Tail mages would then have to unite to fight against this new and powerful threat.
The 'king of fighter vs street fighter graphic novel' is probably filled with intense storylines. You can expect to see how the different fighting styles and power levels of the characters interact. For example, Ryu from Street Fighter might face off against Kyo from King of Fighters. It gives fans of both series a chance to see their favorite characters in a new and exciting setting.
While we can't completely rule out the possibility, it seems very improbable for an official love story to develop between Ryu and Chun - Li in Street Fighter's future. The brand has a certain image and set of expectations. Their characters are so iconic in their own right, with their own goals and values that don't really lead towards a romantic relationship in the traditional sense. But who knows, with the evolving nature of storytelling in video games, perhaps there could be some very minor hints or nods in that direction in the far future, but not a full - blown love story.
A third plot idea is a crossover with the 'Final Fantasy' universe. Ryu could be transported to a world filled with magic and monsters. He would have to team up with the Final Fantasy characters to fight against a common enemy, perhaps using his Hadouken in combination with magic spells.
It depends on the situation. If Mr Bison could quickly use his Psycho Power to control Natsu's mind, he might win. But if Natsu gets close enough to use his fire - dragon - slayer magic, he could deal a lot of damage to Mr Bison.
The plot typically involves the clash between the characters from Street Fighter and Dark Stalkers universes. It might be about a power struggle or some kind of threat that forces the two groups of characters to face off. Maybe there's a powerful artifact or a malevolent force that draws them into conflict.
In a fanfiction, their relationship could also develop through shared experiences outside of fighting. Say they both get involved in a community project in their respective villages. They start to understand each other's values and goals in life, not just in combat. This helps them see each other in a new light and their relationship can grow from there. They might start to communicate more, and over time, feelings of friendship or more could emerge. Also, they could have misunderstandings at first, like Ryu thinking Chun - Li is too strict in her training methods while Chun - Li might think Ryu is too reckless. But as they work through these differences, their relationship deepens.