One idea could be a crossover with the Teenage Mutant Ninja Turtles. The Power Rangers and the Turtles could team up to fight a common enemy like an alien invasion that threatens both their worlds. They could exchange fighting techniques and learn from each other's teamwork.
Well, in such fanfiction, there could be a crossover where the Power Rangers visit the Naruto universe. They might be amazed by the different villages and the ninja way of life. They could then team up with Naruto and his friends to protect Konoha from a common threat. This would involve a lot of cultural exchange between the two groups, with the Rangers showing off their modern technology and the Naruto characters demonstrating their ninja skills.
One interesting crossover could be the vampires from Twilight having to face off against the Power Rangers' villains. The vampires' superhuman strength and speed might be a match for the Rangers' combat skills.
Another possibility is that the villains from both universes team up. The Joker could make a deal with Rita Repulsa. Batman and the Power Rangers would then have to put aside their differences in fighting styles and ideologies to take on this combined threat. The Rangers' zords and Batman's gadgets would both be crucial in this epic battle.
One interesting crossover could be the combination of the unique fighting styles. In RWBY, the characters have their own distinct combat techniques based on their weapons and semblances. Power Rangers, on the other hand, have their signature martial arts moves and the use of their Zords. A crossover could see the RWBY characters learning from the Power Rangers' teamwork in operating the Zords and the Power Rangers adopting some of the RWBY's more acrobatic combat styles. For example, Ruby's speed could be enhanced with the Power Rangers' technology, and the Red Ranger could learn Ruby's scythe - wielding skills.
In a Power Rangers and Spider - Man fanfiction crossover, perhaps the Green Ranger has a special connection to Spider - Man. The Green Ranger's power coin gets corrupted by some sort of dark magic from another dimension. Spider - Man, with his scientific knowledge, helps the Power Rangers figure out how to cleanse the power coin. In the process, they have to battle evil versions of the Power Rangers that are being controlled by the dark magic. The Rangers and Spider - Man use their unique abilities, like the Rangers' morphing and combat skills and Spider - Man's spider - sense and web - slinging, to overcome this threat.
Well, in some fanfictions, the Power Rangers' morphers might get combined with magic from Harry Potter. Imagine a Ranger being able to use a wand to enhance their morphing abilities. Or perhaps the Hogwarts houses could be related to different Ranger teams. Gryffindor Rangers could be the bravest, Hufflepuff Rangers the most loyal, etc. There could also be a story where Voldemort teams up with a Power Rangers villain, creating a super - evil force that the heroes from both universes have to fight against.
One interesting crossover could be the characters from Naruto learning the martial arts styles of the Jungle Fury Power Rangers. For example, Naruto might be intrigued by the way the Rangers use their animal spirits in combat and try to incorporate it into his own ninja techniques. Another crossover could involve the villains. Maybe a powerful Naruto villain teams up with a Jungle Fury enemy to create chaos in both worlds.
One interesting crossover could be the wizards from Harry Potter using their magic in the world of the Power Rangers Samurai. For example, Hermione could use her knowledge of spells to help the Power Rangers in a battle against a powerful enemy that combines dark magic and the forces the Rangers usually fight.
One interesting crossover could be the Rangers' combat skills combined with Fairy Tail's magic. For example, the Red Ranger might team up with Natsu from Fairy Tail. Natsu's fire - based magic could complement the Red Ranger's fighting style. They could face a common enemy that requires both physical combat skills and magical abilities to defeat.
A fanfiction plot could be about a new threat that is specifically targeting the Omnitrix and the Power Rangers' power source. Ben and the Rangers have to figure out how the enemy is doing this and stop them. Along the way, they discover a hidden connection between the two power systems that was unknown before. There could be some character development for both Ben and the Rangers as they struggle to protect what they hold dear.