I treated mine with a routine 10 minute leg soaking in warm soapy water, then I scrubbed off as much dead skin, & scales as possible on the first go. Sometimes picking is necessary for some of the dead stuff in order to get it off.
Second step was petroleum Jelly to smother the legs. I did...
Yep, that's scaly leg mites. Just did a 3 day treatment for one of my hens with a nasty case of scaly leg mites like your's. Mine was just alittle bit worse.