Mainly βωμολόχος, I think? But also ἀλαζών in some episodes?
Socrates, I'd say.
Diogenes of Sinope is maybe closer? He was sort of a living meme and there's a significant volume of apocryphal anecdotes of hijinks and pseudepigraphical writings, going on long after his death.
Definitely Diogenes, 100%
Nooo...it has to be Margites from Homer's Margites :)