When we notice his face has human like, but too big to fit through the earth. So, he’s more of an alien.
He was a humanoid scientist before the ending of the last universe.
Galactus was a humanoid alien called Galan from the planet of Taa
What is it with you and making posts where you answer your own question?
To make a simple explanation where I get to know their history.
@Dr. Nice he actually originates from two cosmos before since we are now on eight cosmos
Galactus changes form depending on the species that views him. The audience, and by extension the characters, are human, thus view him as humanoid.
That was my explanation on which character is human not from earth.
What do you think?