Goku's fighting style might become more fluid. Female characters are often depicted as having more grace in movement, so Goku as a girl could incorporate some elegant dodges and strikes into her already powerful combat techniques.
Goku's character development might involve her becoming more aware of her femininity. She could start to notice how others perceive her differently and use it to her advantage in battles. For example, she might use her opponents' underestimation of her because she's a girl to surprise them with her strength.
Goku becoming a God of Destruction could mean a new look for him. Maybe his Saiyan armor would transform into something more fitting for a god, with a more regal and powerful appearance. His power level would skyrocket, and he could start to have an influence on the balance of the universe. He'd also likely have to deal with other gods, which would lead to some interesting interactions.
With his son Gohan, the relationship could be strained. Gohan has always looked up to Goku as a hero. But as Kakarot, Goku might push Gohan to be more like a traditional Saiyan, which could be too much for Gohan. Also, Vegeta's view of Goku would change. Vegeta has always seen Goku as a rival but also respects him. As Kakarot, Vegeta might see him more as a threat to the Saiyan way of life or as a potential ally in a more Saiyan - centered agenda.
One possibility is that Goku starts to remember more of his Saiyan past as Kakarot. Maybe he begins to have flashes of his original mission on Earth, which was to destroy it. This could create an internal conflict within him as he has grown to love Earth and its people. He might struggle with his identity, trying to reconcile the ruthless Saiyan warrior Kakarot was supposed to be with the kind - hearted Goku he has become.
In the fanfiction, Percy might be chosen by some divine force to become an angel. As an angel, he may have to face the challenges of living in the celestial realm while still having ties to the mortal world. He could struggle with his new identity and the responsibilities that come with being an angel, such as guiding lost souls or fighting against evil forces that threaten the balance between the two worlds.
Well, one possibility could be that Harry Potter, through some sort of magical accident or powerful spell, gets transformed into Goku Black. He might then use his newfound Saiyan powers along with his wizarding knowledge. For example, he could use magic to enhance his ki blasts or use ki to perform spells in a more powerful way. He might also struggle with the evil tendencies of Goku Black while trying to hold on to his own moral compass as Harry Potter.
One idea could be that as a girl, Goku has to face different social expectations in the Saiyan community. For example, Saiyan males might underestimate her at first, but she quickly shows her strength in training and battles, surprising everyone. Another plot could involve her forming new relationships. Maybe she has a different dynamic with Vegeta as a female, like a more sisterly or competitive relationship. Also, her journey to master new forms could be different. Since she's a girl, she might approach the mental and physical aspects of transformation in a new way.
One possible scenario could be that Goku Black starts to see the value in the lives he once thought of as insignificant. Maybe he befriends some of the Z - fighters and begins to understand the concept of protecting rather than destroying. For example, he could start to train with Goku and Vegeta, learning their ways and slowly changing his mindset.