I think Naruto and Levi would be really interesting. Naruto's positive and determined attitude would contrast with Levi's more stoic and no - nonsense personality. They could learn a great deal from each other. Naruto could teach Levi about the power of friendship and believing in oneself, while Levi could show Naruto some of his amazing combat skills and discipline.
Sakura and Mikasa would be a fascinating pair. Both are strong female characters. Sakura has her medical ninjutsu skills and her own combat abilities which she has developed over time in Naruto. Mikasa is a highly skilled fighter in Attack on Titan. They could bond over their experiences of protecting their loved ones. Maybe they could even train together and combine their skills, like Sakura teaching Mikasa some basic medical knowledge while Mikasa shows Sakura some of her unique combat moves.
It has to be Naruto himself. His never - give - up attitude and his ability to make friends easily would make him a great addition to the world of Attack on Titan. He could inspire the characters in that world, like Eren, to keep fighting even in the face of despair. Also, his unique powers would be really cool to see against the Titans.
I think Hinata and Mikasa would make a great pairing. Hinata is gentle but strong - willed, and Mikasa is extremely protective. They could bond over their loyalty to their friends and loved ones. Another interesting pairing could be Kakashi and Erwin. They are both great leaders. Kakashi with his wisdom and combat experience, and Erwin with his strategic mind. They could work together to plan attacks against the Titans or any other threats in the crossover world.
It's hard to say. Thor has his godly powers and his hammer Mjolnir which gives him great strength. But in the 'Attack on Titan' world, Eren's Titan form is also extremely powerful. However, if we consider all - around power, Iron Man with his advanced technology and ability to constantly upgrade his suit might be the most powerful. He could analyze the Titans' weaknesses and come up with strategies to take them down.
One interesting interaction could be between Optimus Prime and Erwin Smith. Optimus, with his strong sense of leadership and justice, would likely respect Erwin's strategic mind and his willingness to sacrifice for the greater good. They could exchange ideas on leading their respective groups in the face of great danger. Another would be between Bumblebee and Eren. Bumblebee's friendly and curious nature could contrast with Eren's often - brooding and determined self. Eren could be amazed by Bumblebee's technology and abilities, while Bumblebee could be intrigued by Eren's Titan - shifting power.
I think Iron Man and Armin would be an interesting pairing. Iron Man with his brilliant mind and high - tech gadgets could learn a lot from Armin's strategic thinking. And Armin could be amazed by Iron Man's technology and learn new ways to fight the Titans.
Levi Ackerman would be an interesting choice. His exceptional combat skills and no - nonsense attitude would make him stand out in the Destiny universe. He could quickly adapt to the Guardians' fighting styles and weapons. His precision with the blades could be compared to the Guardians' accuracy with their guns. And his loyalty to his comrades would be an asset when dealing with the various factions in Destiny. He would be intrigued by the different races and the concept of the Light, and would likely use his skills to protect those in need in the new world.
Eren could be really interesting. Given his ability to transform into a Titan, he might be curious about Godzilla and try to understand his power. He could also see Godzilla as a rival in terms of power and might try to prove himself by interacting with Godzilla in some way.
Naruto and Eren would be an interesting combination. Naruto is full of optimism and determination, while Eren has a deep - seated hatred for the Titans. Their different personalities could create some great character dynamics. Naruto could inspire Eren to be more positive in his fight against the Titans, and Eren could show Naruto the harsh reality of the world he lives in.
Naruto and Rick would be a really interesting combination. Naruto's optimism and never - give - up attitude could inspire Rick, who has seen so much horror. And Rick's leadership skills and survival instincts could teach Naruto a thing or two about dealing with a post - apocalyptic world. They could work together to lead their respective groups and fight off the walkers and any other threats.
Naruto and Rias would be really interesting. Naruto's straightforward and determined personality combined with Rias' leadership and strategic mind could lead to some great interactions. They could learn from each other's fighting styles and ways of dealing with problems in their respective worlds.