One idea could be that Naruto and Gwen are brought to a parallel universe where they have to team up to defeat a common enemy. They could combine Naruto's ninja skills with Gwen's magical powers to create unique battle strategies.
Maybe they meet during a multiverse event. Gwen is intrigued by Naruto's determination and Naruto is fascinated by Gwen's different world. They start to learn from each other, like Naruto teaching Gwen some basic ninja stealth while Gwen shows Naruto new ways to use his chakra with her magic knowledge. This could lead to a deep friendship and many adventures together.
Another plot could be that a villain has a device that can absorb powers and is targeting both their worlds. Naruto and Gwen, along with their respective friends, must find a way to stop this villain. Along the way, there are cultural clashes and misunderstandings that they have to overcome, but ultimately they succeed through their combined efforts and the new bonds they've formed.
One idea could be that Naruto is somehow transported to Spider - Gwen's universe. He teams up with her to fight a common enemy, like a powerful villain who has the ability to manipulate chakra and spider - powers. They learn from each other's fighting styles, with Naruto teaching Gwen about ninjutsu and she shows him some new acrobatic moves.
Perhaps a plot where a powerful villain uses a device to swap the powers of Naruto and Gwen. Naruto has to figure out how to use Gwen's spider - powers while Gwen has to deal with Naruto's ninja abilities. This would lead to a lot of comical and action - packed situations. They would also have to find a way to reverse the power swap and defeat the villain who caused it in the first place.
One idea could be exploring how Gwen's friends and family react to the news. Some might be overjoyed while others could be worried. Another plot could involve Gwen dealing with the physical and emotional changes during pregnancy while also trying to maintain her normal life, like her hobbies or job. And a third could be about the father's role, if known, and how their relationship evolves during this time.
One plot idea could be that they finally kiss after a long period of secretly having feelings for each other during a dangerous mission. When they think they might not survive, they confess their love through that kiss.
Perhaps Gwen discovers she has some latent magical ability during her pregnancy, which is awakened by the life growing inside her. This could cause a stir in Camelot as magic is feared. Merlin then has to step in to help Gwen control her powers and keep it a secret from those who would harm her. Also, Arthur could be faced with the dilemma of how to protect Gwen and the baby from the anti - magic sentiment in the court.
One plot idea could be a story where Peter Parker and Gwen Stacy team up to stop a new super - villain in town. This villain has the power to manipulate time, and they have to figure out how to overcome this power while also dealing with their own feelings for each other.
Maybe in the fanfiction, Spider - Gwen gets lost in the future where Spider - Man 2099 exists. He has to help her get back to her own time while also protecting his own version of New York from the chaos her presence might bring. They could learn from each other's fighting styles and develop a unique bond in the process.
Perhaps in the fanfiction, Gwen is trapped in an alternate dimension where the laws of physics are different. Spider - Man has to figure out how to adapt his powers to that dimension to save her. He could also encounter some strange creatures there that he has to fight off while making his way to Gwen. This would add an element of mystery and adventure to the story.
Maybe a plot where Ash's Pikachu gets lost and Gwen, using her magic skills, helps Ash track it down. Along the way, they encounter some new and strange Pokemon species that are attracted to Gwen's magic. They then have to figure out how to get Pikachu back without causing any harm to these new Pokemon.
One plot idea could be that Peter and Gwen team up to stop a new villain in town who has the power to manipulate time. This would put their relationship to the test as they have to make quick decisions in different time - warped situations. Another idea is that Gwen discovers a new side of Peter's powers that he himself was unaware of, leading to them exploring and training together to master this new aspect.