Well, there's 'The Human Champions'. In this fanfiction, humans form a special team with unique abilities that rival the Saiyans at times. They use their wits and training to take on powerful foes. Also, 'Humanity's Ascent' is interesting. It shows humans evolving their fighting styles and technology to become an important force in the DBZ cosmos, rather than just being overshadowed by the Saiyans and other powerful races.
You can start by checking out fanfiction websites like FanFiction.net or Archive of Our Own. Use the search function and type in keywords like 'DBZ', 'human', and 'useful'. This should bring up a list of relevant fanfictions.
One good one might be 'Gohan and 18's New Adventure'. It explores their relationship in a new and exciting way, with Gohan's Saiyan powers and 18's android abilities coming together in unique battles and situations.
One good dbz human oc fanfiction could be those that focus on a human character with unique powers in the Dragon Ball Z universe. For example, a story where a human oc has the ability to manipulate time in a small way, which creates interesting plot twists as they interact with the main DBZ characters.
One useful Sherlock fanfiction could be 'A Study in Pink: The Fanfiction'. It might offer new perspectives on the characters similar to the show. Another could be 'Sherlock's Hidden Cases' which might explore untold stories. And 'The Baker Street Boys' could be great as it might focus on the relationships between the main characters in a unique way.
One idea could be exploring the life of a human who gains Saiyan-like powers through some scientific experiment gone wrong. They then have to learn to control these new powers while hiding their secret from the world.
You need to focus on character development. As the human transforms, their personality should also change or evolve. Show their internal thoughts and feelings during the transformation. Also, include exciting battles and interactions with other Dbz characters. Use vivid descriptions of the transformation process, like the glowing energy and the physical changes.
There's a fanfiction where a young boy becomes a Lucario. In this story, it explores his journey of adapting to his new form. He has to learn how to use his newfound speed, strength, and aura - reading abilities. It also delves into how he interacts with other Pokémon and humans in his new state.
There's also 'Rosalie and Emmett: The Human Years'. This fanfiction delves deep into their personalities as humans. It portrays Emmett as a strong - willed but gentle man and Rosalie as a confident and beautiful woman. Their story unfolds in a small town where they face various challenges together.
Well, 'Perry and Doofenshmirtz: The Human Side' is quite interesting. It delves into what would happen if Perry was more human - like in his emotions and how Doofenshmirtz would react to that. Then there's 'A Day in the Life' which shows a normal day for both Perry and Doofenshmirtz but with a human Perry twist. Perry has to deal with human - like problems like getting to work on time and Doofenshmirtz tries to take advantage of this new Perry. Also, 'The Great Adventure' is a fanfiction where human Perry and Doofenshmirtz go on an adventure together, exploring places they've never been before and learning more about each other along the way.
Some fanfictions may focus on her relationships as a human. Maybe she has a complicated friendship or a budding romance. These types of stories can be really interesting as they show a different side of her character in a human context.