It's hard to say, but Goku would be a top contender. His ability to constantly power up and reach new levels of strength like Super Saiyan God and Ultra Instinct is insane. But Ben in his Alien X form from the Omnitrix also has near - omnipotent powers. So it could really go either way depending on how the fanfiction writer sets up the battle conditions.
All Kings were not the strongest characters in Dragon Ball. Although Quan Wang had the ability to destroy the universe in Dragon Ball Super, his strength was not impressive. According to the combat power ranking, the strongest character in Dragon Ball Super was the Great Divine Priest. He belonged to the Angel Clan and had extremely strong combat power. In addition, there were other powerful characters in the Dragon Ball Super, such as the guards of the whole king and the angels. Their strength also exceeded the whole king. Therefore, it could be said that the whole king was not the strongest character in Dragon Ball.
It's likely to be Goku. His ability to reach Super Saiyan levels and beyond gives him an insane amount of power. In comparison, even the strongest quirks in My Hero Academia seem relatively weak. Goku's combat experience and his constant pursuit of getting stronger would make him a dominant force in the merged universe.
Basically, Broly is this super strong Saiyan. He gets into battles with Goku and Vegeta. His power is crazy strong. In the end, he stops being a threat and starts to be more friendly with the others.
In a combined fanfiction universe, it could be Whis from Dragon Ball Super. He is an angel who is extremely powerful and has knowledge far beyond most characters. He could potentially use his knowledge of the multiverse and his own powers to outwit and overpower anyone. Although Sailor Moon has the power of the Silver Crystal and Goku has his Saiyan strength, Whis' ability to manipulate time and space, as well as his overall power level, might make him the most powerful character. However, it also depends on how the author of the fanfiction wants to balance the powers of the two universes.
It's a tough call. Goku from Dragon Ball Super has the ability to reach insane power levels like Ultra Instinct. But on the other hand, Acnologia from Fairy Tail is extremely powerful with his dragon - like powers. However, if we consider the potential of Saiyan power growth and Goku's ability to adapt in battle, he might have an edge over Acnologia in a long - drawn fight.
" Dragon Ball: Super Saiyan 10 " was a manga created by the Japanese manga artist Akira Toriyama. It told the story of the main character, Fliesa, who was summoned to become Super Saiyan 10 and fought with Sun Wukong and the others.
Fliesa was an evil cosmic being who had super power and ability. In order to rule the universe, she constantly pursued power. After obtaining the power of Super Saiyan 10, Fliesa became even stronger and fought fiercely with Sun Wukong and the others. In this battle, Fliesa was finally defeated by Sun Wukong and ended his evil reign.
The theme of the story was peace and friendship. It showed the courage and sense of justice of Sun Wukong and others, and also revealed the threat of evil forces in the universe.
Gula was a character in Dragon Ball Super. He was Flisa's older brother and had higher strength and potential than Flisa. Gula appeared in the movie version and Dragon Ball Hero, and showed his powerful combat ability. His form was more advanced than Flisa's, and he had even forced the Super Saiyan into a desperate situation. Gula's strength and potential were obviously higher than Fliesa's, but he disdained to compete with Fliesa for the throne, so he did not become the emperor of the universe. Although Gula appeared in the movie version, his strength and character status made him included in the official history of Dragon Ball. All in all, Gula was a powerful character with potential, and he had a complicated relationship with Flisa.