One idea could be that Link, from Legend of Zelda, somehow gets transported to the Naruto universe. He might initially be mistaken for a strange shinobi with his unique green tunic and hat. Link could use his combat skills, like swordsmanship and shield defense, to team up with Naruto and his friends against common enemies, such as the Akatsuki who are after powerful artifacts. Maybe the Ocarina of Time has some sort of power that the Akatsuki wants, and Link has to protect it while in this new world.
Some great Legend of Zelda crossover fanfiction concepts include a crossover with the Sonic the Hedgehog series. Link could be racing through the Green Hills Zone on Epona. A crossover with the Super Mario Bros. universe is also a fun idea. Link and Mario could join forces to rescue Princess Zelda and Princess Peach from the clutches of their respective villains. Additionally, a crossover with the Kingdom Hearts series would be epic. Link could interact with Sora and the other Keyblade wielders, exploring different Disney and Zelda worlds together.
It could be about Link ending up in Equestria and teaming up with Twilight Sparkle to fight a new evil that threatens both their worlds. Maybe Ganondorf has found a way to enter Equestria and is causing chaos, and Link uses his combat skills while Twilight uses her magic to drive him out.
The relationship between the sages in Legend of Zelda and the Kage in Naruto could be interesting. The sages, with their connection to the elements and ancient magic, could offer their wisdom to the Kage. The Kage, in return, could provide protection and resources. For example, the Fire Sage could collaborate with the Fire Daimyo in Naruto's world. In terms of individual relationships, Tenten might be fascinated by Link's arsenal of weapons and try to learn from him. And Shikamaru might find Zelda's strategic thinking in combat and magic usage very interesting, and they could have long discussions about battle tactics.
First, decide which other universe you want to crossover with. Then, think about how the characters from both worlds will interact. For example, if it's a Zelda and Star Wars crossover, how would Link react to a lightsaber? Next, plan out your plot. Will it be an adventure to save both worlds? After that, start writing the introduction, introducing the setting and the main characters from both universes. Don't worry too much about making it perfect at first. Just get your ideas down on paper.
Link and Twilight Sparkle would be obvious main characters. Link with his skills in combat and exploration, and Twilight Sparkle with her powerful magic and intelligence. They could form an unlikely duo to face challenges.
The characters would interact in many interesting ways. Natsu, being hot - headed, might challenge Link to a fight at first. But then they could realize they are on the same side against a common enemy. Lucy would probably be fascinated by the magic and technology in the Zelda world and try to learn more about it. Zelda, on the other hand, could be intrigued by the Fairy Tail mages' powers and their guild system. She might see it as a way to better protect her own world.
One idea could be Link crossing over into a modern world. He'd be confused by the technology like cars and cell phones. Another could be Link teaming up with a character from another game, like Mario. They could combine their skills to defeat a common enemy.
Mario would be a great character to include. He's from a very different game world, and seeing him interact with Link could be really fun. Another good one could be Sonic. His speed and Link's combat skills could make for an interesting combination.
I really like the fanfiction where Link and Zelda are in an alternate universe. In this story, they are not royalty and adventurer in the traditional sense. Instead, they are ordinary people living in a small village. But, they still have that special connection that draws them together when an ancient evil from the Zelda lore starts to surface. It gives a fresh perspective on their characters.