I've had scaly leg mite problems in the past. I used different remedies. Some natural, some not. And while I fiddled and faddled with natural remedies, my birds lived in misery, but since they cannot speak, I was never bothered by it.
I've dipped their legs in motor oil only to have them slide off the roost and lay eggs that smell like the Indy 500 pit stop. I used Vaseline. I used a custom made concoction that the pharmacist whipped up for me. None of it worked.
Finally I quit fooling around and pulled out the big guns. I Eprinexed the flock (was also treating for lice and fowl mites at the same time). Eprinex is not a one time cure. Eprinex is a commitment to re-apply at timed intervals. But it was the only thing that worked. Once I got the crawlers and their descendants of laid eggs under control, I hung a no pest strip in the hen house.
I used the big guns to beat back the enemy, then hung a No PEst barrier that keeps them away. This takes time and effort. But it worked. My bird's legs are clean as a whistle.
If you want to go the natural route, there are many on here who have and they will share their methods with you. But for me, at some point, I realized the bugs were winning and I'd better up my hand, or give up. And I don't give up without a fight. HOpe you find something that helps. If not, buy a bottle of Eprinex (now brace for Sue who will say it doesn't work. I don't think she was doing it right)
SUE, I see we were posting at the same time! Oil. Ha ha, you kill me!