Well, it might make some characters fear him. Since the Elder Wand is so powerful, some wizards could be worried that Harry might become too powerful and turn to the dark side. For example, the Ministry of Magic might keep a closer eye on him, which would strain his relationship with them.
His relationship with the professors could be very different. Some professors like McGonagall might be intrigued and want to study this new form of magic. Others, like Snape, might be more suspicious and think Harry is up to some new form of mischief or dark magic. This would create a whole new dynamic in the Hogwarts environment.
In some fanfictions, the Elder Wand can make characters overly ambitious. For example, a wizard who gets hold of it might start believing they are invincible and begin to make rash decisions. They might try to take over the wizarding world, thinking the wand's power will protect them from all opposition.
The Elder Wand is a key plot device. Its changing ownership creates a lot of tension and action. For example, when Voldemort tries to gain control of it, it sets off a chain of events that leads to many battles and confrontations.
The fusion could be shown as a chaotic yet beautiful event. Sparks could fly from the wands as they touch, and the magic within them could seem to fight at first, like two different forces trying to assert dominance. But then, as they start to meld, the chaos gives way to harmony. The colors of the magic, say the warm red - gold of Harry's wand and the cold, steely grey of the Elder Wand, could blend into a new, unique color. And the resulting fused wand would look as if it was crafted by the most skilled wand - maker, with an otherworldly beauty and an aura of great power.
The Elder Wand choosing Harry has a huge impact on the plot. It gives Harry an edge over Voldemort. Since the wand is the most powerful, it makes Harry a more formidable opponent. It also adds an element of destiny to the story, as if Harry was meant to be the one to defeat Voldemort all along.
A broken wand can change the story in many ways. For instance, it can limit a character's magical abilities, forcing them to rely on others or find new ways to be useful. This can lead to new character dynamics and plot twists.
The different wand might change his abilities in terms of spell specialization. Say the new wand has a different wood that is attuned to certain types of magic. If it's a wand made of willow, which is often associated with healing magic, he could find himself more proficient in healing spells, even if he wasn't before. This would be a significant shift in his magical abilities as he would be able to contribute in a different area of magic within the wizarding world.
Maybe he discovers some ancient spells or incantations that don't need a wand. These could be spells that were forgotten over time but are still effective. He spends time researching in old books and uncovers these wand - less magic techniques.
It could lead to a complete transformation of their relationship. They might become allies, working together against common enemies. The act of giving the wand could be the catalyst for them to let go of past grudges and form a bond based on shared values and goals. This could involve them sharing secrets, protecting each other, and even becoming friends outside of the immediate conflict situation.
The story would change drastically. Harry would be without his main means of magic. His enemies might take advantage of this. For example, Voldemort would see it as an opportunity to attack. Harry would have to rely on his wits and the magic he can do without a wand, like some basic spells he might have learned instinctively. His friends would also be more protective of him, and they might have to work harder to keep him safe.