I've read some head canons about IronMan Lena and I love them. And I have this idea that while Kara knows that Lena is also a superhero, because duh, she could recognize her girlfriend's eyes anywhere, the gang doesn't know and they are still a little bit wary about Lena, mainly Alex and James. So one day, during game night there is an emergency, some kind of robbery or hostage situation, and Kara is the first one to put her suit and go to the rescue while the rest stays in the apartment watching the news. Suddenly one of the bad guys pulls out a strange gun which emits greenish light and everyone knows what that means. Thee apartment is now a frenzy of activity but before Alex or James can make their way out, Lena is already activating her suit and flying out of the window. The gang just freeze in their places watching the news again and seeing how IronLena (because I can't think of a superhero name) is fighting the guy with kryptonite gun and helping Supergirl save the day. And that's how everybody understand that LENA IS GOOD.