no one mentioned
Bokutachi ga Yarimashita (tldr: mc did yagami light thing, but just once)
its not really about heros or antiheros, but rather raises some morality questions, there are no bad or good guys, only victims and it sure blends all the possible lines between right and wrong, reminded me of Dostoevsky's Crime and Punishment
and definitly one of the brightest (not literally) delinquent character out here for
some reason, not the main one
also, a list of antiheros by definition:
The World Is Mine
Aku no Kyouten
Me-Teru no Kimochi
Sayonara Zetsubou Sensei
Wendy maybe also freesia, dont remember for sure, same author
Asano Inio's
guess its kind of a spoiler and also not so true, but actually is by defenition because of some later plot twists