Naruto would probably be very cautious around Aizen at first. He's used to facing powerful enemies, but Aizen's deceptive nature would be a new challenge. Aizen, on the other hand, might see Naruto as an interesting specimen, someone with a strong will and great power that he could potentially manipulate.
If they were to fight, Naruto would likely start with his standard attacks like Rasengan. Aizen would likely dodge effortlessly with his superior speed and then start to taunt Naruto, trying to break his spirit. But Naruto would not be deterred and keep coming back, which could annoy or even intrigue Aizen. As the fight progresses, Naruto might start to sense something is off about Aizen and try to figure out his true intentions.
In a non - combat situation, Naruto might try to befriend Aizen. He believes in the good in everyone and would want to understand Aizen's past and what led him to become the way he is. Aizen would be amused by Naruto's naivete at first, but Naruto's unwavering belief could start to make him question his own actions and motives over time.
Aizen would likely try to deceive Naruto at first. He's a master of manipulation, so he might pretend to be a friend while having ulterior motives. Naruto, being naive in some ways, might initially believe Aizen. But as time goes on, Naruto's sharp instincts would kick in and he'd start to question Aizen's true intentions.
The Soul Reapers would be very confused at first. They are used to Aizen being a certain way, and Naruto's different personality would be a shock. Ichigo might be curious and see Naruto - Aizen as an ally against the common enemies. Orihime could be one of the first to trust Naruto - Aizen because of his kind - hearted nature that she would sense. And the Espadas would probably be on high alert, not knowing what to expect from this new Aizen.
They might have a mentor - student relationship. Aizen, with his vast knowledge and power, would be in the position of a mentor, guiding Naruto. Naruto, being eager to learn and grow stronger, would be the student. However, there could be some tension as Naruto has his own sense of justice which might conflict with Aizen's more self - serving motives at times.
The storyline could start with Naruto somehow ending up in Aizen's world. At first, he would be confused and on guard. But as he gets to know Aizen, he might see some potential in him. Naruto would try to change Aizen from the inside. Aizen, on the other hand, might see Naruto as a useful tool or an interesting experiment.
Naruto would probably be very curious about the succubus. He might start by asking a lot of questions. He's not one to be easily intimidated, so he'd likely approach her without much fear.
Naruto would probably be very curious about Gandalf. He'd be asking a million questions about Gandalf's staff, his magic, and his long beard. Gandalf, on the other hand, might be intrigued by Naruto's determination and the strange power of chakra. He could see Naruto as a being with great potential for good in a world full of darkness, just like Frodo in Middle - earth.
Naruto would probably be very curious about Android 21. He'd likely approach her with his usual friendly and open - minded attitude. Android 21 might be a bit reserved at first, but Naruto's enthusiasm could break the ice. They could start by just talking about their different abilities.
Naruto and Android 21 might interact in various ways. At first, Naruto would probably be very curious about Android 21. He's used to dealing with all kinds of strange things in his world, but Android 21 would be a whole new level. Android 21 could be interested in Naruto's physical abilities and chakra system. She might try to approach him in a friendly way to study him, but Naruto, being a ninja, would be cautious. Eventually, they could either become friends if Android 21 proves she has good intentions or remain enemies if she tries to harm Naruto or his friends.
Naruto would interact in a very enthusiastic way. He'd be in awe of the Avengers' powers and would want to learn from them. At the same time, he'd show off his own ninja abilities. He might bond with Hulk over their shared 'rage' - like Naruto has his nine - tailed fox anger and Hulk has his own. He'd also try to cheer up the more serious Avengers like Black Widow with his positive attitude. And he'd probably try to get them all to do some ninja training together.
Naruto would probably be very friendly and curious towards Tohka. He might start by asking her a lot of questions about her powers and where she's from.