I have a similar problem, it's a cross hatching in the shadow area from the raw file and jpg.
Also shadow noise is quite bad even at iso 100.
Did a test of shadow noise from base iso 100 up to 3200, it really fell apart from 800iso onwards.
And when looking at the raw in photos hop this cross hatching seemed odd to me.
As this is my first drone and tiny Sony sensor I'm not sure if this is typical or faulty?
Having waited over 48 hours for Parrot to reply I thought I'd ask on here.
Cheers in advance.