Perhaps in the fanfiction, Goku teams up with a human fighter from Record of Ragnarok. They could combine their fighting styles, like Goku teaching the human how to harness ki while the human shows Goku some new hand - to - hand combat techniques.
Some fanfictions also play with the idea of alliances. Maybe some gods team up with humans against other gods, or different groups of humans form unexpected partnerships. This changes the power dynamics and the overall plot structure, leading to very exciting and unpredictable stories.
Loki would also be a difficult adversary. He's very cunning and could use his tricks and illusions to try and outwit Goku. Goku would need to rely on his senses and ki to see through Loki's deceptions.
One interesting 'Record of Ragnarok Fanfic' could be about a new character entering the Ragnarok battles. For example, a demigod who has unique powers that no one has seen before. This new character could change the whole dynamic of the battles and create new alliances or rivalries among the existing fighters.
One interesting fanfiction could be about the reactions of the human side when a new and unexpected god shows up to fight. For example, how they strategize and what their initial thoughts are.
A Goku crossover with the Pokémon world could be really fun. Goku could try to catch Pokémon using his speed and strength. He might also team up with Ash to battle powerful Pokémon trainers. Or how about a crossover with the Digimon world? Goku could enter the Digital World and help the Digimon in their battles against evil Digimon using his energy attacks.
One idea could be a crossover where Goku somehow ends up in the RWBY universe. He could train the RWBY characters, sharing his martial arts knowledge and helping them improve their combat skills. For example, he could teach Ruby how to better control her speed and use her scythe more effectively in combat.
One idea could be a story where Goku and Kefla have to team up to face a new, powerful enemy that neither could defeat alone. They start off not trusting each other much, but as they fight side by side, they learn to respect one another's strength and fighting styles.
One idea could be that Goku and Goku Black are forced to team up against an even greater threat from another universe. They start to understand each other's fighting styles during the battle and gradually develop a grudging respect for one another.
In some versions, the female Goku could be part of a prophecy. The two Gokus meet, and at first, there is some confusion and misunderstanding. But as they get to know each other, they discover that they are key to fulfilling the prophecy. They combine their powers and defeat an ancient evil that was threatening both of their worlds.
One interesting plot idea could be the exploration of Asgardian characters' reactions to Thor's journey in Ragnarok from a different perspective. For example, how the common Asgardians felt about Thor's battles and his newfound friends. Maybe some of them were skeptical at first but then became inspired by his growth.