Pulling out the picked on one will just make it harder for her - she'll have to readjust back into the flock all over again.
I would remove the JG for at least a week so that pecking order can reestablish without her and see if that changes things for the Faverolle - also make sure to cover up any red with blukote to discourage pecking.
If things go well without the JG, reintroduce her after a week-10 days and see if that does the trick. If she's still mean, she goes. If the other birds still pick on the Fav while JG is in detention, then maybe they sense something off about the Fav.
Also, make sure your chickens have plenty of room and distractions, feather picking often starts with boredom...'ho hum, nothing to do, hey, that beard looks different...let me go peck at it...'
I would remove the JG for at least a week so that pecking order can reestablish without her and see if that changes things for the Faverolle - also make sure to cover up any red with blukote to discourage pecking.
If things go well without the JG, reintroduce her after a week-10 days and see if that does the trick. If she's still mean, she goes. If the other birds still pick on the Fav while JG is in detention, then maybe they sense something off about the Fav.
Also, make sure your chickens have plenty of room and distractions, feather picking often starts with boredom...'ho hum, nothing to do, hey, that beard looks different...let me go peck at it...'