Having been an aviary bird, it will certainly take a lot longer to establish a relationship with her.
To gain her trust your aim is to start pairing “good things” with your presence… like favourite foods. By the same reasoning causing her to flutter around, pairs your presence with an aversive. So try to do everything you can to keep her body language as relaxed as possible… whether that is keeping still/moving slowly and smoothly, or avoiding direct eye contact as Spearmint suggests. The only way to approach my then “fearful” Amazon, Ollie, was to definitely avoid eye contact and I had to crawl to his cage to avoid having him flap around in panic. I crawled because birds feel safer higher up where they can see approaching predators. The bird can’t get any higher in a cage, but you can get lower. So that’s how I serviced his cage.
Also if you are having to use subtracted reinforcement to get her back into her cage, that is also going to erode trust. If this is the case, see if you can let her out maybe an hour or so before breakfast, when she is hungriest, so that she flies back in when she sees you slot in the breakfast bowl. Again I used to do this with Ollie - it worked so well that I could do this before work and then in the evening too. Gradually he was out for increasingly longer periods of time.
What foods does she favour? You could try wedging something big between the bars of the cage like apple if she likes it… or millet spray. When she begins to come eat straight away, get slower at wedging it so that eventually she is eating from it whilst you are still holding on. Then you can try offering through the open door. Then make the item gradually smaller so she is getting nearer and near to your fingers. The process may take as long as a few months or it may be faster. Take your cue as to when to move to the next stage from her - ie only move on when she’s totally comfortable with the last stage.
When she’s comfortable taking treats from your hand you can certainly begin to train her using favourite foods as reinforcement for behaviours you want to see more of.