That used to work several years back, but it doesn't anymore. People are too shallow these days. I mean, we have Tinder ffs...People don't even have to interact and reject and say no anymore. They just swipe left and let a computer generated algorithm do it for them before a conversation even gets going.
What I mean is...if I'm looking to make friends, I'm probably not really going to find friendships on dating and hookup sites and applications because the predominate reason why people are on dating sites and hookup sites in the first place is pretty much entirely for shallow and selfish reasons. I mean, I could make a shallow and selfish friend that way...bbbuuutttt that's a dime a dozen scenario from Hell, and you're gonna have a bad time (South Park reference). I mean I can't really tell you what the answer is for you, because what works for me probably won't work for other people, but I find friends either at/through work, or through common interests and/or discussions of common interests either online or (admittedly) though very rarely these days, at a bar, after I've had a couple drinks, and someone approaches me for some reason instead.
If you're looking to make friends with the opposite sex just for like inquiry purposes as to how they think, just relax and be yourself and talk to them normally and respectfully. Keep the conversation engaging and interesting. If you're looking to do it for ulterior motive, it doesn't quite work like that. But if you wanna meet people just to meet people? That's totally fine. You won't seem awkward or threatening if you aren't
acting awkward or threatening. Don't open mouth, insert foot, because nobody likes that. If you do, don't beat yourself up over it because it can (and will) happen, and then you just try again and try NOT to do that the next time.