If Batman is in Wonder Woman's body, his relationship with Aquaman could change. Aquaman is used to dealing with Wonder Woman in a certain way, but now he'd sense a different approach. Batman would also have to navigate Wonder Woman's relationship with the gods. This could be a huge challenge for him as he doesn't have the same connection to the divine. When Wonder Woman is in Batman's body, she would change how Batman is perceived by Commissioner Gordon. Gordon might find this new 'Batman' more approachable and less brooding. And she would likely have a different way of dealing with the rogues gallery in Arkham Asylum.
The story could start with some sort of magical or scientific accident that causes the body swap. Batman would suddenly find himself in a female body with super strength and a lasso of truth. He'd have to figure out how to use these new abilities while also maintaining his identity. Wonder Woman, on the other hand, would be in the dark and gritty world of Gotham. She'd probably use Batman's gadgets in a more straightforward way than he does, and her presence would likely change the dynamic between Batman's allies and enemies.
If Naruto is in Sakura's body, his relationship with Sasuke might change. Sasuke might be initially confused by the 'new' Sakura's more Naruto - like behavior. Naruto might also have a different perspective on how Sakura views Sasuke. For Sakura in Naruto's body, her relationship with Kakashi could be different. Kakashi might notice the change in 'Naruto' and be more cautious. Also, Naruto's friends like Shikamaru might be puzzled by the sudden shift in 'Sakura's' personality.
If Ash was in Serena's body, his relationship with her friends like Bonnie and Clemont would change. Bonnie might be a bit confused as Ash's more boyish and impulsive nature shows through Serena's body. Clemont might be surprised at some of the battle - like decisions Ash makes when dealing with things like helping around the lab. On the other side, if Serena was in Ash's body, her relationship with Ash's rivals like Gary would be different. Gary might be intrigued by the more refined and composed 'Ash' he now sees.
Another way is through personal challenges. Let's say Batman faces a personal crisis that only Superman and Wonder Woman can help him with. This could lead to a deeper emotional connection. Superman might open up more about his alien heritage and the loneliness he sometimes feels, and Wonder Woman could share her experiences from Themyscira. As they support each other, their relationships grow.
Their relationship could become more trusting. Since Batman saves Wonder Woman, she might start to see him as more than just a brooding vigilante. She could open up more to him and share her fears and secrets.
Let's start with the Avengers. In Spider - Man's body, Jane would interact with the Avengers in a unique way. She would bring her scientific knowledge to the table, which could be very useful in some situations. However, her different personality might cause some friction. For example, Iron Man might be intrigued by the new 'Peter' but also a bit annoyed at the different approach. Captain America might see the change in 'Peter' as a sign of him growing up in a different way. On the other side, Spider - Man in Jane's body would have to deal with Asgardian friends and foes. He would befriend some of the more adventurous Asgardians, but also face the jealousy of some who don't like this 'outsider' in Jane's body. Overall, their body swap would create a lot of chaos and interesting changes in their relationships with other characters.
After the proposal, their relationship would likely become more public. They would no longer be just comrades in arms but an engaged couple. Their interactions would be more affectionate and they would start planning a future together.
Their relationships would change significantly. For instance, their friends might be very confused at first. Spider - Man's friends would see the Wasp acting differently in his body, and vice versa. Their romantic relationships, if any, would also be affected. They would have to explain the situation to their loved ones, and it could lead to some awkward or comical moments.
Wonder Woman and Damian's relationship could start as a mentorship of sorts. Damian, being young and still learning, would be in awe of Wonder Woman's power and grace. As time goes on, they could become friends, with Wonder Woman teaching Damian about different cultures and values. Batman, on the other hand, might be initially a bit protective or jealous of their relationship, but eventually come to see the benefits for Damian.
If Anakin and Obi - Wan swapped bodies, their master - apprentice relationship would be turned upside down. Obi - Wan in Anakin's body would have to deal with Anakin's more impulsive nature and his connection to Padmé. Anakin in Obi - Wan's body would have to take on the role of the more level - headed mentor, which would be a huge adjustment for him. Their interactions with other Jedi and in battles would be very different as they struggle to adapt to each other's personalities and abilities.