What a playful silly girl.
Well, she is definitely barbering her feathers. Not a single feather in any of your three pictures is naturally molted. I was hoping to see a mixture of both thinking her molting was irritating and causing the barbering but I see no evidence of natural molt.
One cause could be her scissor beak but in truth it should be more difficult to barber with that condition. She seems to line up the bottom beak pretty well when she preens, no? Is the bottom beak not level or is there a gouge that could be causing this? Maybe a piece that is snagging the feathers causing her bother?
Her baby noises and squeals are completely normal to me. None of her sounds are distressing. Playful blue and gold talking is all I hear. Scratching and messing with her ears... ???? While I want to say normal we are searching for something abnormal to pin point the issue. A slight yeast or bacterial infection could cause an imbalance of pressure in her ears. It could also irritate her enough to be uncomfortable and pull at her feathers. Considering she is still handfeeding it is extremely possible she could have a fungal or bacterial infection.... so...
My suggestion is to get her in to see a vet and lets see a cbc, fecal sample and mouth swab. Might be a good time to have the vet do her beak again anyway.
I know the vet is not the easiest thing where you live. It's actually not been easy for US residents lately either. Bring a few feather pieces with to show the vet and run a few simple tests.
She is just so stinking cute though! Such a little personality. Plenty of mischief going to be had in your house.