"The ones in my world go through a lot to hide who they are. Voice modulation and masks and stuff. I'm pretty sure they don't want people knowing who they are." In fact she knows they don't. Oliver is really particular about who knows his secret. Like got in trouble for telling particular. "Besides, personally I don't do masks unless a party calls for it." She's still not lying, just not directly saying she knows superheros or works with them. Besides, Oliver and the others aren't technically a superhero. That would be Barry ... who she, works with, from time to time.