In some fanfictions, Goku Black has been depicted as having a hidden power reserve. In the Tournament of Power, he could tap into this reserve and achieve a new level of transformation. This new form would give him increased speed, strength, and energy projection. He might use this form to take on multiple strong opponents at once, like the powerful warriors from Universe 7 or other universes. His attacks could become more unpredictable, such as his energy beams changing direction mid - flight to catch his foes off - guard.
Then, introduce some shared experiences. Maybe they get trapped in a strange dimension together. In this new and dangerous place, they have to rely on each other's strengths. Goku's physical power and Frieza's cunning could be the keys to their survival. As they go through these experiences, they start to see each other in a new light and their relationship begins to change.
Hit would also make for a fascinating pairing. Hit is a skilled assassin with time - manipulation abilities. He could be a great foil to Goku Black. Maybe Goku Black tries to outwit Hit in his time - stop techniques, or they could form a temporary alliance based on their mutual desire to eliminate certain opponents in the tournament. There would be a lot of cat - and - mouse action between them.
One idea could be that Goku Black forms an unexpected alliance during the Tournament of Power. Maybe he teams up with a weaker universe's fighter out of a sense of pride, thinking he can make them strong enough to be a worthy opponent. Another could be that Goku Black discovers a new form during the tournament that is unique to this alternate version of himself.
If Broly joined the Tournament of Power, it would be an absolute game - changer. His raw power is off the charts. He could easily take on multiple opponents at once. He might start by targeting the strongest foes, like Jiren. His uncontrollable rage could work in his favor, as opponents would be intimidated. However, his lack of teamwork skills could also be a drawback. But with his power, he could probably just brute - force his way through many battles.
In some lemon fanfiction, their interaction can be filled with tension. Goku, being the good - natured Saiyan, may be initially wary of Frieza. But as the story progresses, they might find common ground. For example, they could start to respect each other's power.