Adaptation is a major theme. The characters in the fleet of fog have to adapt to the new rules and situations in the crossover. Also, discovery is common. They discover new powers, new species, or new technologies during the crossover. It makes for very interesting storylines as they figure out how to deal with these new things.
It might not be exactly what you want, but I would recommend a novel that is most relevant to your description: " The Story of a Ship Girl from Another World " is a light novel written by the author, who knows who. It is a derivative Doujinshi novel. The general plot of this novel is as follows:
In the world of the fusion ship R and C, the deep sea occupied 85% of the ocean. This was the story of an admiral leading his ship to fight back against the deep sea.
" Admiral, the target sea area has been cleared."
"Return."
"Report, we still have strength left. I think we can still…"
"Return."
"... First formation, change course!"
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" Ship Girl: From Deep Blue to the Sea of Stars " was a light novel written by the author, Wang Zixu. It was a fantasy novel. The general plot of this novel was:
Traversing the Ship Girl World, building modern ship girls, obtaining modern technology, revitalizing the Middle Fleet, eliminating the deep sea crisis, integrating the Ship Girl World, and heading towards the sea of stars...
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" Doomsday Voyager " was a sci-fi and doomsday crisis novel written by the author's pen name. The general plot of the novel was:
The age of sailboats, the age of behemoths!
Build ships and cannons!
Add cannons to the side of the ship, steer, fire!
It was the beginning of the era of naval warfare.
Snatching the population who could farm, developing the deserted island, and traveling the four seas!
A small boat hanging alone in the sea, huge waves and storms, ghost ships carrying ghosts and dead objects, sails swaying in the storm, and cannon fire that cut through the darkness together with lightning!
。
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The book " Commander of the Blue Sea Route Mixed Fleet " was a light novel by the author, Withered Mountain Woodcutter. The general plot of the novel was:
In the beginning, the three of them, Little Cutie I19, Big Eye Moe, Nagashima, Nicholas, Ayanami, Lafite Port Area's four wastes, Kaga bb, Tiancheng, and Avatar, fought with wits and courage... As one problematic ship girl after another joined the fleet, Li Feng's daily life gradually began to collapse. QQ Book Group: 901502136, everyone is welcome to join.
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" The King of Messy Voyages " was a sci-fi time-travel novel written by a bunch of mosaics. The general plot of the novel was:
The first volume: The Great Voyage, the second volume: Drifting on Lanlan Island, the third volume: Chaos Without Morality, the fourth volume: The Item of Praise-The Mask of Hypocrisy, the fifth volume: The high school daily life of all kinds of anime female protagonists...
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" The Ship Girl in the Dust " was a light novel written by the author, Extreme Black and White. It was an original fantasy novel. The general plot of this novel was:
When people were chasing the mighty Bismarck, Yamato, and Howard, who would remember those ship girls in the corner? They also had flesh and blood, joy and sorrow. However, they were so weak that they never had a voice of their own. The admiral who had transmigrated to another world would hold all the ship blueprints and all-purpose modification devices to create a different world of ship girls.
QQ group: 174109877.
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" The Ship Maidens of Deep Blue " was a light novel written by Admiral Deep Blue. The general plot of the novel was:
The ship is in line with the hegemony, and the ship is in line with the deep blue! This was the story of a conqueror admiral coming to the world of ship girls, reorganizing the world-destroying fleet, and continuing to dominate the deep sea. Everyone is welcome to comment on his new book,'The Visitor of the Heavens of Games.' [P.S. 2: The readers can chat about the plot in the reader exchange group.]
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" The Battle of the Blue Seas " was a military-war fantasy novel written by the author, Cold Moon Rushuang 2. The general plot of this novel was:
Runbai, who was touring on a battleship, accidentally fell into the water and transmigrated to a planet that was similar to the real world but different. He appeared in a medium-sized land country with limited resources and was surrounded by the sea. Under the watchful eyes of various powerful countries, let's see how he will lead the empire to the top of the world with advanced naval concepts.
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" Ship Girl's Journey to the Other World " was a light novel by the author, Mozi Rhythm. The general plot of this novel was:
On that day, the world was in danger and was invaded by darkness. He became a member of light and defeated darkness.
After that, when he woke up again, he came to a magical world.
The girls here were actually running around on the sea with huge turrets on their backs? They were called Ship Maidens!
Then, what were these sea monsters? They were called deep-sea ships!
Hey, hey, where did this high-tech shipgirl organization called Siren come from?
…
To put it simply, this was a protagonist with the light factor. He brought his girls to various foreign worlds to watch.
The story of fighting with the Siren...
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" The Rise of the Elves from the Water Fleet " was a light novel by the author, Dumb Tingshou. The general plot of the novel was:
The members of the old fleet, Gaiokayds, for the power of the ocean, charge! The members of the water fleet of the new era, I'm a great pirate who roams the ocean! [PS: The original world, reality, and Pokémon Doujinshi.]
One interesting concept could be the interaction between the unique powers in 'Bleach' and the technology or abilities within the 'Fleet of Fog'. For example, how would a Soul Reaper's zanpakuto fare against the advanced weaponry of the Fleet of Fog ships.
Rukia could also be a main character in this crossover fanfiction. Her knowledge of the Soul Society and her own unique powers could add a lot to the story. She could form an interesting relationship with some of the more robotic - like characters from the Fleet of Fog, perhaps teaching them about the concept of souls and the afterlife.
Well, perhaps the 'Fleet of Fog' enters the wizarding world and the wizards initially mistake them for some new kind of dark magic creatures. Harry and his friends then have to figure out what they are and find a way to either make peace or drive them away. The wizards could use their magic to try and understand the technology of the Fleet of Fog, like Ron trying to figure out how their engines work with a simple 'Engorgio' spell on some of the parts to see what happens.
I think Neville could be an interesting main character in this crossover. He has grown so much in the Harry Potter series, and his knowledge of plants could be used in some unique ways against the Fleet of Fog. For example, he could use some magical plants to either hide Hogwarts from the Fleet of Fog's sensors or use them as a form of defense. From the Fleet of Fog, a young and curious engineer could be a main character. They would be fascinated by the magic and would try to figure out how to incorporate it into their technology. Ginny Weasley could also be a main character, with her strong will and magical abilities.
One great 'fleet of fog crossover fanfiction' story is 'The Fog's Encounter'. It combines elements in a really interesting way. The characters from different parts of the fleet of fog universe interact in unexpected scenarios, which makes it a thrilling read.
Flower Is Not Flower, Fog Is Not Fog was an adaptation of the online novel " Fog House ". The TV series was based on the novel.
The drama told a bizarre Jianghu story about the love story between the protagonist Mo Yu and Blooming Flowers Pavilion. Mo Yu was an ordinary university student, while Blooming Flowering Pavilion was a mysterious character. He had the power to control flowers and trees.
The drama was about 30 minutes long, and the plot was compact and emotional.
Flower Is Not Flower, Mist Is Not Mist was a famous web novel with a total of 27 episodes. The plot of episode 27 was as follows:
At the beginning of the twenty-seventh episode, the protagonist Fang Yun accidentally discovered a woman named Li Ruoxin who seemed to be inextricably linked to him. Fang Yun tried to get close to Li Ruoxin, but Li Ruoxin kept a distance from him, which made Fang Yun feel confused and painful.
In the following plot, the relationship between Fang Yun and Li Ruoxin gradually deepened, but Fang Yun's father suddenly appeared and interrupted their relationship. Fang Yun was forced to go back to the past and recall his love story with Li Ruoxin.
At the end of the 27th episode, Fang Yun finally solved the problem between himself and Li Ruoxin, but he found that Li Ruoxin had died, leaving only a letter expressing her last wish and love. Fang Yun was deeply moved and decided to continue his life under Li Ruoxin's guidance.