There are a considerable number of Dragon Ball manga. It's a long-running and popular series, but the exact count might vary depending on how you classify different editions and spin-offs.
The universes can blend through power - based interactions. For example, the ki energy in Dragon Ball Z could interact with the magic in Frozen. A scenario could be that the Dragon Balls are used to try and fix a magical imbalance in Arendelle caused by some dark magic. The Saiyans' ability to sense energy could also be used to detect hidden magical sources in the Frozen world.
They blend the universes by incorporating the power systems. For instance, in some fanfictions, characters might use Devil Fruits while also having the ability to sense and use ki. Also, character interactions play a big role. Luffy's carefree nature might influence Goku's more straightforward approach to life.
They often blend the two universes by having characters cross over. For example, Naruto could end up in the 'Dragon Ball Z' world and start learning about ki and fighting Saiyans. Or a 'Dragon Ball Z' character could visit the Hidden Leaf Village.
The number of Dragon Ball manga books is quite substantial. It includes the main series and various spin-offs. But the precise number can change based on how they're categorized and published.
Dragon Ball manga consists of 42 volumes. Each volume contributes to the rich and exciting world of Dragon Ball, featuring memorable characters and epic battles.
As of now, there are a specific number of Dragon Ball Super manga volumes, but it's constantly evolving. You might want to check the latest updates from official sources.