In this crossover fanfic, the main characters would be a mix of both universes. Lincoln would be a key character as he is curious and might stumble upon the connection between the two worlds. His sisters like Leni, who has a unique view of the world, could also be important. From Totally Spies, Sam, Clover, and Alex are the mainstays. But I think Rita and Lynn Sr. from The Loud House could also have a role. Maybe they are the ones who first notice something strange going on that leads to the discovery of the crossover situation, and the spies would then rely on their help as adults to navigate the Royal Woods and its secrets.
Obviously, the main characters from The Loud House like Lincoln, who could be the one to bridge the two worlds together. And from Totally Spies, Sam, Clover, and Alex. They would be the main characters as they are the core of the Totally Spies team. Maybe Lincoln's sisters like Luna and Luan could also play important roles, like helping the spies with their local knowledge or unique skills. For example, Luna could use her music to communicate secret messages or Luan could use her pranks to create distractions during a mission.
Well, perhaps a mad scientist creates a portal that connects the two universes of The Loud House and Totally Spies. The Totally Spies are lured into the portal and end up in Royal Woods. They meet the Loud family and soon realize that the same scientist is planning to use a powerful device in Royal Woods to control the minds of people all over the world. The Loud kids and the spies then form an alliance. The spies teach the Loud kids some basic self - defense and spy techniques, while the Loud kids show the spies how to blend in with the local community and use everyday objects as tools to stop the scientist.
One idea could be that the Loud sisters get recruited by WOOHP. Maybe Lincoln accidentally discovers a WOOHP gadget and the spies come to retrieve it. They notice the Loud sisters' unique skills and talents. For example, Lori's bossy nature could be useful for leading missions, and Leni's fashion sense could help with disguises. They all team up to stop a villain who is using a new technology to take over the world.
I think Lincoln from The Loud House and Sam from Totally Spies could team up. Lincoln is smart and good at coming up with plans, and Sam is the most level - headed of the spy girls. They could work well together. Also, Lola and Clover might team up. Lola is all about beauty and winning, and Clover is stylish and confident. They could use their charm to distract villains while the others do the more action - packed parts of the mission.
Dr. Octopus could be a great main antagonist. He could team up with a female super - villain from the Totally Spies universe. Together, they could create a plan to steal some top - secret technology. Dr. Octopus uses his mechanical arms to cause chaos in the city, while the female villain uses her own unique powers to keep the Totally Spies and Spider - Man at bay.
In a crossover with Danny Phantom, Danny would be a key character. His ghost - fighting abilities and the Totally Spies' skills in dealing with more earthly threats could combine in an interesting way. For example, they could face a villain who has the ability to phase between the ghost zone and the human world, and Danny and the spies would have to use their respective skills to stop him.
Sam, Clover, and Alex are the stars of Totally Spies. Sam has a great sense of logic and is good at analyzing situations. Clover brings the style and charm to the team, and she's not afraid to use her looks to her advantage during missions. Alex, on the other hand, is always ready for action and her enthusiasm often gives the team an extra boost.
It could be the Joker. Imagine the Joker getting involved in a global scheme and teaming up with some international bad guys. His chaotic nature would be a huge challenge for both Batman and the Totally Spies. He would use his usual tricks like laughing gas and mind games, but on a much larger scale.
One possible plot is that a mad scientist creates a device that can manipulate time. This device falls into the wrong hands and starts causing chaos in both Gotham and the places where the Totally Spies operate. Batman and the spies get caught in the time - warped events. They have to figure out how to reverse the effects while also dealing with the changes in the timeline that are making their enemies stronger. The fanfic could explore how they adapt to these changes and use their unique abilities to save the day.
A possible plot could be that there is a threat to the world that involves both superpowers and high - tech espionage. The Totally Spies are called in to investigate the technological aspect, while Spiderman is already on the scene dealing with the super - powered part of the threat. They cross paths and at first are not sure if they can trust each other. But as the situation worsens, they realize they need to work together. They combine their unique skills, like Spiderman's web - slinging and the Totally Spies' ability to blend in and use advanced gadgets. In the end, they defeat the common enemy.
One idea could be that the Totally Spies are sent on a mission to investigate some strange paranormal activities. They then discover Danny Phantom's world and team up with him to stop an evil force that is using both magic and technology to take over the world. Danny could teach them about the Ghost Zone and they could share their spy skills with Danny.