Eating too many feathers can clog up the system. I hate when my birds eat feathers, and I'm constantly picking up after them during a molt. Anyway, for impactions you can use Baby Oil (mineral oil) about 1 ml 2X daily for a day or two, it will help break down stiff things that might be clogging up the gizzard. Stool softers like plain Dolculax (Docusate Sodium only ingredients) works too if the mineral oil doesn't help. Prick a pill open and squeeze (with pliers) onto something she will eat or into some apple sauce or baby food in a syringe and squeeze into the mouth, 2 times a day. These things won't hurt her if this isn't the issue. Definitely feed her soft wet things only like scrambled eggs, watermelon, wet greens. Impactions generally move with a lot of added water.She is not bullied. The only thing I can think of is that she likes to eat feathers just for no reason, and there is an abundance of them due to the molt.
What I'm just concerned about is potential permanent slow crop or permanent blockages or something. I know its not a tumor probably, because this crop thing appeared suddenly.