Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 16 - 16-77. Saga Empire, Battle at the Imperial Capital (7)

The end of all worlds approaches.

The Demon King Order harvests lives from all manners of living beings.

Within this darkness full of despair,
A single person escaped from space-time, returned to before the world collapsed, determined to change the fate of the past.

But as time pass, he gradually finds out that the Apocalypse isn’t quite as simple as he thinks…

In the era of surging big pirates, pirates are evil? Is the navy justice?

The green pheasant seals the sea, the yellow monkey turns on the lights, and the red dog ignites!

Backed by the three major admirals of the navy, the captain of the Destiny Pirates, the legendary fisherman, the veteran card dog, and the new Pirate Emperor Cui Ze Fite said, of course—

Victory is justice!

- Description from novelbuddy

Set in a Pokéverse where the remnants of our civilization's Earth lie buried under the resurgent human/Pokémon societies, this epic Saga follows the protagonist through his journey to the heights of Pokemon Training and beyond, across a planet that was only saved from ecological disaster by an act of Arceus. As Humanity and Pokémon coexist in this fusion of settings, the story will explore themes of war, oppressive cults, and Shadow infusion, in a world where Pokémon healing and battles echo the anime in realistic, but not overtly graphic ways. Pokémon do not rip each other apart in Battles, though it can sometimes happen in the wild.This is a very long journey fic that's kind of a Crossover with everything. But with Pokémon. So you might see characters like Shaggy Rogers, or Izuku Midoriya, but with Pokémon teams. Pokémon legends like Red, Gary Oak, and the reigning World Champion, Ash Ketchum, are also, naturally, present in the setting. Think of this slice of the Pokéverse as one where it's all coming together.

When Su Jiu dies on her eighteenth birthday, she transmigrates into a novel about painful love and becomes an adorable four-year-old child.