If Harry Potter meets his lawyer in fanfiction, it could be really interesting. The lawyer might be a Muggle - born wizard who has a very different view on magic laws. He could introduce Harry to new ways of thinking about the laws in the wizarding world. For example, he could point out that some of the old pure - blood - favored laws are actually discriminatory and need to be changed. And Harry, with his influence, could start a movement to reform the wizarding legal system.
It could be depicted as a rather comical scene. Harry, all confused in his wizard robes, sitting in a Muggle - like office filled with law books and the lawyer trying to explain complex legal jargon to him.
Perhaps his grandparents were great adventurers in their time. They could have traveled to far - off magical lands and encountered strange and wonderful things. Their experiences could be passed on to Harry, inspiring him to explore more of the wizarding world and its secrets. They might also have been involved in some great battles in the past, and their war stories could give Harry valuable lessons for his own fight against Voldemort.
One possibility is that Harry's grandparents help him uncover his family's true history. They could show him old family portraits and explain the relationships and events that led to the present situation. His grandparents may also have a different perspective on the fight against the dark forces. They could advise Harry on how to use his powers more effectively and how to build alliances. And they might even be the ones to finally reveal the full story behind the prophecy related to him.
There could be an entirely new goblin character created just for this fanfiction. This goblin lawyer could be an outcast from the goblin community because of his more progressive views on wizard - goblin relations. Harry, seeing his potential, hires him to help with his legal battles that require a fresh perspective.
It could be Hermione. She's always been very book - smart and she could have decided to study law in the wizarding world. She already has a great understanding of the rules and regulations at Hogwarts, so it would be a natural progression for her to become a lawyer. And she would be very dedicated to helping Harry with any legal issues.
Luna Lovegood might be an unexpected but interesting choice. She has a unique perspective on the wizarding world. While she may seem a bit eccentric, her ability to think outside the box could be useful in a courtroom. She could come up with creative defenses for Harry, and her calm and dreamy nature might be able to sway a jury or judge in Harry's favor.
Another theme is justice. Harry, being the hero we know from the original series, is always striving for justice in these fanfictions. He uses his legal skills to right wrongs and protect the innocent in the wizarding world. For example, in many of these stories, he defends those who are wrongly accused of using dark magic.
One possible plotline could be Harry using his knowledge of the wizarding laws, which he learned through his years at Hogwarts and his experiences with the Ministry of Magic, to defend wrongly accused wizards in a wizarding court. Another could be him trying to reform the wizarding legal system which he might find full of loopholes and biases.
Hermione Granger could be a common character. Given her intelligence and knowledge of the wizarding world laws (she's always reading), she could easily be imagined as a brilliant lawyer. She would use her quick thinking and vast magical knowledge to build strong cases.