So basically Oda has said in the SBS that the Love-Love fruit(Boa's fruit) works via any emotion and not just lust. It just happens that Hancock's sexy which is why people who suffer from the petrification is because of lust.
This explains why Blackbeard would want it and also debunks that the fruit in anyway makes the user more appealing in the physical sense. My question is if it's any emotion why wasn't Luffy affected?
(I don't really remember the scene but wasn't he angry? Ik he's asexual but if it's any emotions his anger shoulda enabled the power to work on him. Or am I remembering if wrong?)