How to ask for feedback from fellow dancers?

How to ask for feedback from fellow dancers?

This individual wants to ask for feedback, but feels too awkward after the dance to ask.

I think asking right after one dance would put someone on the spot. It can be tricky to come up with helpful advice so quickly. I would recommend asking someone after a few dances with them.
You can say something like “Hey that was fun! I’m trying to get better; do you have any feedback for me?”
Or
"Hey, I'm looking to improve. Do you have any constructive feedback for me about how I dance? Don't worry I won't be offended by anything you say. I'll just use it to improve for next time"

Of if you want an opinion on something specific ask about that, “How was my Tension/frame/styling?”

I would put value of opinion in this order.
1st: My Instructor / Teacher. They should be the ones who are guiding you on your path.
2nd: I would video record myself dancing, and value what my eyes deem good vs. bad.
3rd: The opinion/feedback from others. ESPECIALLY in the beginner stage. Asking another beginner what they think can have its merits, but it’s like asking a baby what they think about politics. It doesn’t know enough to give you a valid opinion. Now if the dancer is proficient and you actually value their opinion, then definitely ask. But I would take feedback from beginners with a grain of salt / skepticism.

I think it’s best to ask feedback in the class setting. If after the class there may be 15 mins of social dancing time. Like I said earlier get someone to record you, and then you can analyze what you see. Mistakes are glaring in video.