I asked yesterday about Xenophanes' argument (is there one?), because it seems to me that the fragments are today standardly taken to express an indifference argument, but I don't see that that is the only, or most plausible, alternative.
The move is well displayed by McKirahan's commentary. This is the argument as he reconstructs it:
...we Greeks think the gods have the appearance of Greeks, yet all other peoples portray the gods as having the distinctive characteristics of themselves; but a god cannot simultaneously have the characteristics of all human peoples, and there is no reason to prefer one anthropomorphic account to another. More radically, [Xenophanes] challenges the very conception of anthropomorphic gods. In this case too, the belief stems from humans projecting their own nature onto the divine.