Hello and welcome to BYC!
This isn't bumblefoot, which is an infection of the foot pad, you would see a scab on the bottom of the foot on the pad.
This looks like a couple of things. It looks like she has some "leg scale mites" invisible little mites that crawl up under the leg scales and eat them, the scales raise up because the surrounding skin is irritated. If left un treated, birds can get bone infections as the mites burrow into the leg bones.
It also appears she may have early gout.
To treat the mites: I usually start with a warm foot soak and with a tooth brush, I gently scrub the scales just to clean them off. Be gentle and don't break them off. Thorough dry off the feet and apply Vaseline to the scales, gently rubbing so it gets under the scales. You can wipe off the excess Vaseline. Do this every other day for a month, it will smoother the mites.
As for the gout, avoid high protein foods like meal worms, meats and such foods. Try and use the lowest protein chicken feed.
This should help, keep us posted on her especially if you don't see any improvement.