Well, 'A Pirate's Ninja Way' is a great fem Naruto in One Piece fanfic. It has an interesting plot where the female Naruto character ends up in the One Piece world and teams up with Luffy's crew. It's full of action and some really cool character interactions.
The theme of self - discovery is also quite common. Fem Naruto, being in a completely new world, has to figure out who she is outside of her original ninja context. She might question her values, her goals, and her identity, which makes for some really deep and engaging stories as she grows and changes in the One Piece universe.
One common theme is the clash of cultures. The ninja world of Naruto and the pirate world of One Piece have very different values and ways of life. So when a fem Naruto enters the One Piece world, there's often a focus on how she adjusts to the pirate code and the more free - spirited nature of the pirates. Another theme is the exploration of new powers. Since Naruto has unique abilities like chakra control, seeing how these interact with the Devil Fruits and Haki in the One Piece world can be really interesting.
In the fanfiction, Fem Naruto might have some sort of special connection or knowledge. Since Naruto has a strong sense of justice, Fem Naruto would be the same. She might have heard about Ace's situation through some channels and decided to take action. She could use her chakra - enhanced strength to break through any barriers the marines set up to keep Ace captive.
She'd probably fit in quite well. Her strong will and determination are similar to many characters in One Piece. She could use her ninja skills to make a name for herself in the pirate world. Maybe she'd become a sort of legend, like a new type of pirate with ninja abilities.
One interesting plot idea is a fem Naruto being transported to the One Piece world and having to learn the ways of the pirates. She could use her ninja skills in new and unexpected ways, like using chakra to enhance her sword fighting in the One Piece world.
Well, the whole dynamic of the Straw Hat crew would change drastically. Fem Naruto would bring her ninja skills, like shadow clones and chakra control. The crew might rely more on her for stealthy operations rather than Luffy's straightforward attacks. Also, her personality, which is a mix of determination and a bit of a tomboyish nature, would add a new flavor to the crew's interactions.
In a fanfiction where Naruto is a fishman in One Piece, Naruto would face new challenges. For example, dealing with the discrimination that some fishmen face in the One Piece world. But he'd also have new opportunities. He could use his fishman physiology to swim faster and deeper, discover hidden treasures, and maybe even find a way to connect the ninja world with the pirate world. His Nine - Tailed Fox chakra might also have some interesting interactions with the strange powers in One Piece.
One really good 'One Piece Fem Harem Fanfiction' is 'A Pirate's Heart'. It has a great plot where the main character finds himself in various interesting situations with the female characters from One Piece. The character development is well - done and the interactions are engaging.
Her combat skills are top - notch. With her ability to use ninjutsu and taijutsu, she can take on multiple opponents. In the context of saving Ace, she could face a large number of marines. Her skills would enable her to hold her ground and get Ace to safety.