I thought I was going to have to get rid of one bird in this years hatch. But I put in some toys for them (straw, little perches, etc.) Bored chicks can be mean. And now she is super sweet. Easter eggers are usually bullied not the bully themselves. How long did you seperate them? Also how big is your brooder box? Too small of a box can lead to issues.
What worries me is that it is pecking in the eyes and vent, that is usually cannibalism. How old were they when you got them? Where did you get them. Cannibalism can be a problem, if it is you could either cull or re-home. I personally can't get myself to cull, but I wouldn't want to have that chick teach the rest to be cannibals either. So to me that is one reason that I would maybe have to cull. I personally hate culling and I've been lucky enough not to have to so far.
Many people will take one or two hens for the enjoyment and the eggs. Especially in city limits, where they can only have a couple. Another thing is many people don't want to have chicks because the dust and dander in you house/garage, use this for your advantage. Or sell her to someone who wants one chicken for their kids or something. As long as she's sweet to humans. If it's a cockerel somebody could want one just to have a neat looking rooster running around their property. So this could be an option if things don't get worse.
Another option is blue kote, I have heard nothing but good things about it. Except it doesn't wash out of clothes and it is hard to get off your skin so be careful. Also try neosporin on the injured ones if you don't try the blue kote. I usually put neosporin on injured birds seperate it for a day so I can monitor it. Bit if the injury is bad I seperate till it is competely healed. Then I try putting it back in.
I would first try the seperate her and put in some toys, give her some time. It could take a few tries. If it doesn't work ask friends and family help look for someone who would take her. I think you can probably find a solution that doesn't include culling.
