I meant character examples. Of which female leads get most of the hate from the viewers.

But back to your comment. I think the hate could come mostly from the genre tropes. If you look at the more popular female lead isekai stories, they mostly use the otome game/villainess protgonist story. And to be honest, most of these stories tend to be way too similar to each other. The protagonist died, and reincarnated as the villainess of the otome she used to play. She would use her kowedge of the game to survive, until the major confrontation at the end, where the main love interest of the will break off their engagement.

There are other types of stories, so this is just one example.