Maybe you already ran across this article, but thought I'd share.
https://thisnzlife.co.nz/5-reasons-your-chicken-may-be-limping/
And this sounded similar - the vet suggested metacam which is for pain relief. If you can't access that then 5 aspirin to 1 gallon of water can help chicken's with...
She's definitely holding it up and not wanting to put any pressure on it. My guess is that it's broken or dislocated. Could be a pinched nerve? Or maybe arthritis, but, I don't think she'd be holding it up like that. If you want conclusive answers, I'd seek out a vet.
Video is probably best. I only asked about wry neck due to the comment about using her wings to balance. Injuries can take time to heal. Do you think she could have broken her leg at any point?
I'm not seeing raised scales. But, she has some pretty long nails that could be trimmed. Have you checked the bottoms of her feet? Sometimes they jump and land wrong causing a limp that usually heals up fine. If you're worried, maybe separating her in a crate where she can still see her pals...