Well, in the fanfictions, Neville could be one of her allies. Neville has always respected Hermione's knowledge and bravery. He might step up to support her during the Triwizard Tournament, perhaps by helping her with some of the herbology - related tasks or just being moral support. Also, Luna Lovegood could be an ally. Luna's unique perspective and knowledge of the wizarding world's oddities could complement Hermione's more traditional knowledge, and they could work together to figure out the mysteries of the tournament.
Fleur Delacour could potentially be an ally. Despite being competitors, Fleur might recognize Hermione's intelligence and power. They could form an unlikely alliance based on mutual respect for each other's skills. Additionally, Viktor Krum might also be an ally. He was interested in Hermione in the original story, and in the fanfiction, this could lead to him helping her out in the tournament, either because of his feelings for her or because he respects her as a worthy opponent.
Harry and Ron would be her most likely allies. They are her best friends, and even if they might be initially shocked or jealous of her being in the tournament, they would surely come around to support her. Another likely ally could be Cedric Diggory. He's a fair - minded and kind wizard, and he might see Hermione's intelligence and skills as an asset and offer to help or at least be friendly towards her.
There are fanfictions where Hermione and Fleur become friends during the Triwizard Tournament. In some stories, they start to see past their initial rivalries. Fleur might initially see Hermione as just a book - smart girl, but as they face the challenges of the tournament together, they develop a mutual respect. Maybe they work together on the Yule Ball preparations within the context of the tournament, which helps to strengthen their bond.
One possible fanfiction could be about Harry and Hermione teaming up secretly during the Triwizard Tournament tasks. They might use their combined knowledge and skills to outwit the other competitors. For example, in the maze task, they could have a special code to communicate and find their way to the Triwizard Cup faster than anyone else.
Goku could be a likely ally. Despite their initial conflicts, Goku has a way of seeing the good in people. He might approach Broly and convince him that they can work together to win the Tournament of Power for their universe. Their combined strength would be a formidable force.
There might be a fanfic where during the Triwizard Tournament, Harry gets cursed and Hermione has to find a way to break the curse. She races against time, using every spell and potion she knows. Meanwhile, she also has to deal with the tournament tasks on Harry's behalf. In the end, through her determination and love for Harry, she manages to break the curse and they both complete the tournament in an unexpected way.
One common plot is Hermione being an unexpected champion. Maybe she gets chosen by the Goblet of Fire due to some magical interference or a misunderstanding. Another plot could be her facing unique challenges during the tasks. For example, in some fanfictions, she uses her vast knowledge to outwit the challenges in a different way than the original champions. Also, there are often plots where Hermione has to deal with the jealousy and suspicion of her peers, since she's not supposed to be in the tournament in the first place.
Natsu. He's got incredible power and determination. His ability to eat fire and use dragon - slayer magic gives him an edge. He's not afraid to take risks and he's always ready for a fight, which would be very useful in the various tasks of the tournament.
In some fanfictions, Hermione might be developed as more of a rebel. For example, she could be tired of always following the rules in the Triwizard Tournament and decides to break a few to gain an advantage. This shows a different side of her, one that's willing to take risks.
Maybe in the fanfiction, there's a plot twist where Hermione discovers a hidden rule in the Triwizard Tournament that allows her to form an alliance with all the champions instead of competing against them. This would change the whole dynamic of the tournament and lead to a completely different kind of story.
A common plotline is that of Hermione and Fleur teaming up against the other competitors. This is interesting as it subverts the expected rivalry. They can use their combined strengths to overcome challenges that neither could face alone. For example, Hermione's strategic thinking paired with Fleur's beauty - based magic can be a formidable combination in tasks like the maze.
Hermione Granger is often a popular character. Her intelligence and love for learning make her a natural fit for the academic aspect of the Triwizard Tournament. She can be portrayed as using her vast knowledge of magic to outwit her opponents in the various tasks.