There's also 'Female Broly: A New Power'. In this fanfiction, it focuses on how she interacts with the other characters in a different way compared to the male Broly. It shows her as a complex character with her own motives and emotions, which makes it an interesting read.
Well, it gives a fresh perspective. Since Broly has always been male in the original, a female Broly in fanfiction allows for new storylines. For example, she could have different relationships with other characters. Maybe she has a more nurturing side compared to the male version.
Vegeta could also be an interesting choice. Vegeta has his own pride and issues with power, much like Broly. In a crossover fanfiction, they could start off as rivals, constantly trying to outdo each other in terms of strength. But as the story progresses, they might find common ground and have to work together against a common enemy. This would be a great way to explore both of their characters in more depth.
One common theme is power and its control. Since Broly is known for her extreme power in the original series, in the fanfictions with a female Broly, a lot of stories focus on how she manages this power, especially in a world dominated by male Saiyans. Another theme is identity. As a female in a male - centric universe, she often has to find her place and prove herself.
In a Broly - losing - control scenario in a DBZ reader insert fanfic, the story might focus on how the reader's actions affect the outcome. For example, if the reader is a Saiyan as well, they could try to communicate with Broly on a level that other characters can't. They might understand his pain of being an outcast and use that connection to stop his rampage. It could also be that the reader has some knowledge from the future or another dimension that gives them an edge in dealing with Broly.
One popular 'dbz broly x trunks fanfic' is 'The Unlikely Bond'. It explores an interesting dynamic between them as they face a new threat together in a creative storyline.
Another theme is redemption. Given her potentially villainous nature in the original, many fanfics give her a path to redemption. This could involve her making amends with characters she has wronged in the past. It often involves her learning about friendship and loyalty along the way. For instance, she might start off as a loner but gradually form bonds with other Z - fighters.