If you want to keep her, and have her be able to feed herself somewhat- you definitely need to trim her beak on a regular basis. The easiest way to trim (at least for me) will be the same way you have seen with scissor beak in parrots. With a dremmel. You can shape the beak, and will know you have reached the living part before you lop off a big piece like what happens often with nail trimmers. Have on hand styptic power, or even better- a silver nitrate stick to cauterize if needed.
If you do not trim on a regular basis- with severe scissor beak the upper beak overgrows & shoves the lower beak to the side- the chicken version of the TMJ joint dislocates (painful, long term arthritis ect). The pictures posted already look too far gone for the bird to ever be normal, but dremmeling/trimming every 1-2 weeks should allow them to feed them selves somewhat- but they have to to do the shovel method instead of the peck it up method.
Sadly many people think they can eat, as they ARE hungry, and will madly peck at food, but they can't meet their calorie needs and are stunted and eventually starve to death. Pick your bird up at night right before or after it has gone to roost- is the crop full? (full of water doesn't count). if it is not full, more trimming needs to be done, or adjust the feeder, or commit to hand feeding or tube feeding several times a day. Or cull.
I also think trimming a chick is very important- as this is when the bird is growing the fastest- the longer one waits, the more likely permanent damage has been done to the TMJ/jaw joint. You can always go back and shorten or reshape the beak, but if the bird can't open it's beak because the TMJ joint it destroyed, even a perfect beak will not help it eat any better.
Good luck, Jess
and by the way, what you learn from this experience may save someone(or something) elses life.
