One Piece’s Greatest Swordsman

Roger hadn't even set sail yet, and Garp was already a vice admiral. So, in your opinion, he's always been a vice admiral? They clearly grew up together, didn't they?

The author could revise this scene, letting Bit and Roger finish their last drink. Otherwise, it doesn't convey the feeling of "I am the only one who matters"—the world's greatest swordsman.

The first mate of One Piece is pretty good, but it feels like the story was abandoned.

It's pointless. Even after joining Whitebeard, Ace still couldn't find his own path. He's been taken down!

Robin is the real powerhouse right now, okay? There's Shanks, one of the Four Emperors; Buggy, whose fighting power has skyrocketed and whose bounty is probably over 1 billion; and the world's strongest swordsman—the past, present, and future. If she joins Luffy's spaceship, she'll also have Luffy, who's already a powerhouse, following along.

This book title... Could the protagonist be the legendary man who becomes the Pirate King?

Holy crap, this is all made up. Robin was only three or four years old when Roger was alive. If you don't know anything, you should do more research. You can't just write it like this.

Seriously, that's enough. If your imagination isn't enough, just use the original plot.

I'm not satisfied with the writing style; it reads like a high school essay, making it uninteresting to read.

It's at least above average, so why are there so few recommendations?