Harley is more annoying but the Joker is quite annoying too. Never been a fan of both, and I particularly dislike Harley, mostly for the overexposure we had of her since the first Suicide Squad movie.
Joker in the Sense that He's Overshadowing Many DC Villains like Lex Luthor, Reverse-Flash, Hath-Set, Gentleman Ghost, Count Vertigo, Abra Kadabra, Mirror Master, Wotan, and Many More
I am most definitely not a fan of either but i find joker more annoying. liking harley is questionable she is insane was abused by by joker to make her that way and if yall are sayin you like her from suicide squad well she is nothin like harley in the comics because the comics show her true story but again i dont like her ever. also give me one good reason to like either of them.