One idea is that the female Lucario has a special connection to an ancient Pokemon artifact. She has to protect it from evil forces that want to use it for their own gain. Along the way, she meets new friends and overcomes many obstacles.
Another plot could be that the female Lucario gets separated from her group in a strange new region. She has to adapt to the new environment, make new allies among the local Pokemon, and find her way back to her friends while also uncovering secrets about this new region.
Maybe the female Lucario is a trainer's partner, and they enter a unique Pokemon competition that tests not only their battle skills but also their friendship and understanding. This would explore the relationship between the trainer and the Lucario in a different way.
One idea could be the main character being reborn as a Pikachu and having to navigate the world with its electric powers while making friends with other pokemon. Another could be being reborn as a Eevee and having the unique ability to evolve into any form at will, which causes both envy and admiration among other pokemon. Maybe the reborn pokemon has memories of being a human and uses that knowledge to outwit trainers and other threats.
One plot idea could be Lucario's journey of self - discovery during pregnancy. It could explore how it copes with the physical and emotional changes, and how it interacts with its friends and allies in this new state. Maybe it has to overcome some challenges while still protecting its unborn.
A possible plot could involve the male human being a trainer who has a unique connection with the female Lucario. They enter a Pokémon tournament where they face numerous challenges together, not only in battles but also in dealing with the politics and rivalries among other trainers. Their relationship deepens as they rely on each other to succeed.
A possible plot could involve a dark force threatening both the world of Lucario and Equestria. A group of ponies and Lucario have to come together. The ponies use their magic and the Lucario use their combat skills and aura powers to fight off the common enemy. This would show how different abilities can be combined in a crossover story.
One idea could be that Ash discovers a female Charizard that has been separated from its group. He decides to train it, but it has a very different personality from his regular Charizard. Maybe it's more stubborn and has unique battle techniques that Ash has to learn to work with.
One idea could be that Ash discovers a female Mewtwo in a hidden part of a forest. She's initially scared of humans but Ash manages to communicate with her using his bond with Pokemon. They go on a journey together to find a place where she can live in peace, away from those who might want to use her powers.
One idea could be that your female OC is a trainer from a small village in Kanto. She discovers a rare and injured Pokemon that no one has ever seen before. She decides to nurse it back to health and in the process, forms an unbreakable bond with it. This new Pokemon then helps her in her journey to become the best trainer, facing unique challenges along the way.
One great fanfiction could be about a female Lucario's journey to master new Aura techniques. It could involve her training with other Pokemon and trainers, facing challenges and growing stronger. This type of story would focus on her character development and the unique bond she forms with those around her.
One plot idea could be a story where a trainer forms an unexpected bond with Reshiram. Maybe the trainer is initially afraid of Reshiram's power but over time they learn to work together and understand each other.
A plot idea could involve a Phantump that is actually a reincarnation of a human who had a strong bond with Pokemon. The Phantump then tries to find its way back to its human family while facing the challenges of being a Pokemon in a world that doesn't understand its true nature. It could be a heart - wrenching and exciting story.