¿Who is stronger, Zamasu or Galactus?

Zamasu is a significant antagonist in the "Dragon Ball Super" series, known for his complex ideology and formidable abilities. Originally a Kai apprentice from Universe 10, Zamasu becomes disillusioned with mortals, leading him to enact the "Zero Mortals Plan" to eradicate all mortal life. He collaborates with his future counterpart, resulting in the creation of Goku Black by swapping bodies with Goku. Their fusion through the Potara earrings forms Fused Zamasu, a being of immense power but with a deteriorating body due to the fusion of mortal and immortal entities. Zamasu's abilities include energy projection, flight, and a unique form of immortality. His character explores themes of justice, morality, and the consequences of unchecked power within the "Dragon Ball" universe.

Galactus is a comic book character created by Marvel Comics and is known to be one of the publisher's most powerful and feared villains. He is a cosmic being who has come to Earth with the goal of consuming planets and becoming the supreme being in the universe. Galactus has a number of supernatural powers, including the ability to manipulate cosmic energy, the ability to control people's minds and behaviour, and the ability to summon cosmic creatures at will. He is also immortal and virtually indestructible, making him a formidable foe for any hero who confronts him.