He might be more old - fashioned in his ways. His grandparents' values would likely have a big influence on him, so he could be more reserved and traditional compared to the Harry we know from the original series.
Harry could be more family - oriented. Since he was raised by his grandparents, he would have a closer bond with them and value family above all else. This might make him more hesitant to leave home for Hogwarts.
If Harry was raised by his grandparents in fanfiction, his personality would change in several ways. For starters, he would be more self - assured because he'd grow up in a loving environment. He wouldn't have the same insecurities that came from being treated as an outcast at the Dursleys. He'd be more extroverted, as he wouldn't be afraid to show his true self. His sense of humor might be different too, perhaps more light - hearted and less sarcastic as a defense mechanism. He'd also have a stronger sense of family and heritage, which would influence his actions and decisions.
Harry might be more self - assured. Since his grandparents are likely to be more loving and supportive than the Dursleys, he would grow up with a better sense of self - worth. He could be more open - minded as well, because his grandparents' different parenting style would expose him to different ideas and ways of thinking.
He might be more traditional in his magic use as his grandparents would likely teach him older spells. Also, he could be more family - oriented since he was raised by family. He might be less impulsive as his grandparents could have instilled more patience in him.
He might be more shrewd. Goblins are known for their business acumen and cunning. So, Harry could be more calculating in his decisions, not as impulsive as in the original story.
He would probably be more in touch with nature. He might be calmer and more attuned to the environment around him compared to canon Harry.
He would likely be more confident. Growing up with his grandparents, who presumably love and support him, he wouldn't have the self - doubt that came from living with the Dursleys. He would be more self - assured in his magical abilities from the start.
In such a fanfiction, perhaps the story could show Harry growing up with a different kind of family dynamic. His grandparents might instill in him values that are different from what he would have learned at the Dursleys'. For example, they could be more open about his magical heritage from the start, which would lead to him being more confident in his abilities as he grows. Maybe they would also have their own set of magical friends and connections that would introduce Harry to a different side of the wizarding world earlier.
He would be more feral. The Xenomorphs' aggressive and survival - based nature would likely rub off on Harry. He'd be less hesitant in a fight compared to the original Harry, and more likely to use brute force along with his magic.
He'd be more in tune with his instincts. Instead of relying on the social norms of the wizarding world, he'd follow his gut feelings more. For example, in a dangerous situation, he might act like a wolf in a pack, assessing threats quickly and instinctively.
He might be more laid - back. Irish culture has a certain charm and easy - going nature, so Harry could be less uptight than in the original. He could also be more superstitious due to Irish folklore.