A really interesting plot could be that a powerful villain from Mortal Kombat decides to invade the My Little Pony world. The ponies then have to team up with some of the good - hearted Mortal Kombat characters. Fluttershy, being the kind - hearted pony she is, could try to befriend some of the more aggressive Mortal Kombat fighters and convince them to help protect their world too. The ponies would then have to adapt to the much more violent combat style of Mortal Kombat.
A cool plot might be that the villains from My Hero Academia make a deal with Shang Tsung. In exchange for power, they bring the chaos of the Mortal Kombat world to their own. All Might then has to lead the remaining heroes, some of whom learn Mortal Kombat fighting styles, to stop the villains and the new threat from the other universe.
It has to be Spike. He's a small dragon in the My Little Pony world. In Mortal Kombat fanfiction, he could use his ability to breathe fire in really creative ways. He could also use his small size to his advantage, sneaking around and attacking from unexpected angles. His loyalty to the ponies would make him a really determined fighter, which would be quite unexpected considering his usually cute and helpful role in the pony world.
One possible plot could be that some Pokemon accidentally end up in Equestria. The ponies are initially scared but then they realize the Pokemon are friendly. Together, they team up to stop an evil force that threatens both their worlds, like a powerful dark - type Pokemon and an evil unicorn. They use their combined powers of friendship and unique abilities to defeat the enemy.
One possible plot could be that Spongebob somehow gets transported to Equestria. He befriends Pinkie Pie first because of their similar energetic natures. They start having a party together, and Pinkie Pie shows Spongebob around Ponyville. Then, they might encounter a problem like a mysterious spell that's making all the ponies sad. Spongebob, with his positive attitude, tries to help the ponies cheer up and along the way, he meets Twilight Sparkle who teams up with him to find a way to break the spell.
One possible plot could be that Naruto somehow gets transported to the My Little Pony world. He might initially be confused by the colorful and peaceful land, but then he could use his ninja skills to help the ponies when they face a threat, like a powerful dark magic user. He could teach the ponies some of his combat moves, and in return, learn about the magic of friendship from them.
One possible plot could be that Spongebob and Patrick get lost in a magical portal and end up in Equestria from My Little Pony. They meet Twilight Sparkle and her friends. Spongebob's positive attitude and Patrick's goofy nature could create some humorous situations as they try to figure out how to get back home while also getting involved in the local pony adventures, like helping to solve a problem with a magic spell gone wrong.
In a 'pokemon meets my little pony fanfiction', a great plot could be that there's a dark force threatening both the Pokemon and My Little Pony universes. A group of strong Pokemon like Charizard and a team of brave ponies including Rainbow Dash join forces. They travel through different regions of both worlds, gathering allies and learning new skills from each other to defeat this common enemy. It would be full of action, friendship, and discovery.
Perhaps Kenshi enters the Mortal Kombat world during a tournament. He is drawn to the power and chaos of the tournament. He decides to participate not only to test his skills but also to find a way back home. Along the way, he meets Kitana and they form an unlikely alliance. Kenshi helps Kitana with his strategic mind and combat skills, while she teaches him about the politics and power dynamics of the Mortal Kombat world.
One possible plot could be that characters from Game of Thrones are transported to the Mortal Kombat realm. For example, Jon Snow could find himself in a Mortal Kombat tournament. He would have to use his sword - fighting skills learned in Westeros against the likes of Scorpion or Sub - Zero. His Stark - like sense of honor might conflict with the brutal rules of Mortal Kombat.
One possible plot could be that the ponies from Equestria accidentally stumble into the wizarding world of Harry Potter. They could be initially confused by all the magic there which is different from their own. The ponies might try to help Harry and his friends with their unique pony magic, like Twilight Sparkle using her knowledge of spells in Equestria to solve some of Hogwarts' mysteries. And perhaps the Hogwarts students could learn about friendship in a new way from the ponies.