In a fight between characters from Ben 10 and Star Wars, it's a complex matter. Ben's Heatblast form could deal a lot of damage with his fire - based attacks. But a Sith Lord like Darth Maul, with his double - bladed lightsaber and acrobatic fighting style, would be a tough match. If we look at the most powerful in terms of long - range attacks, Ben as Cannonbolt could roll into a ball and cause destruction from a distance. But in Star Wars, a character like Han Solo with his blaster skills could also hold his own. Ultimately, it's difficult to determine who would be the most powerful as both universes have their own unique power systems and characters with diverse abilities.
It's hard to say for sure. Ben with the Omnitrix has a wide range of powerful alien forms. But in the Star Wars universe, characters like Yoda with his mastery of the Force are extremely powerful. If Ben transformed into Alien X, which has near - omnipotent powers, he could be really tough to beat. However, someone like Darth Sidious with his dark side powers and political manipulation skills could also be a formidable opponent.