Eh, while Amanda Palmer has some definite lolcow tendencies and definitely needs to grow up (and this is coming from a fan, mind), I'd say Emilie Autumn is worse. For one thing, Palmer's only really gotten noticeably lolcow-ish over the past few years, from what I've seen, but Autumn's pretty much been like this her whole career. (See also: Trisol.)
Plus Palmer has some degree of lyrical depth beyond "I HATE MEN AND AM TOTES BIPOLAR U GUISE!!!!11111 LOL SO CRAZY", and having seen both of them live, I can also say she puts on a
much better live show, in that hers actually includes her
actually making music. Autumn's shows are basically her doing karaoke of her own songs--she does sing them, but all the instruments are prerecorded. Even her violin, for the most part (I think she took it out for a few songs but for the most part it was canned). And keep in mind that Autumn got her start as a violinist, and actually is pretty skilled there--you'd think she'd put some actual focus on the thing she's really, genuinely
good at, but nope.
Finally, there seems to be a lot more active malice coming from Autumn. Palmer seems more clueless than outright malicious to me (though she's
incredibly clueless, to be fair), but Autumn just seems cruel a lot of the time, so I really can't bring myself to pity her in any way, ever--I just kind of laugh and roll my eyes at her batshittery.
So while Palmer is a bit of a lolcow, I'd say that if you had to compare her and Autumn, the latter is worse. (And honestly, I'm not sure why there's as much comparison between the two as there is, since aside from having somewhat similar aesthetics and belonging to the same basic genre, there's really not a lot in common between their music. Again, this is speaking as someone who listens to both of them.)