@Eggcessive mentioned pinless peepers. A situation in my own flock with an aggressive/flighty hen has me noticing things I haven't observed in nearly 20 years of keeping chickens, and pinless peepers have played a role.
I've used pinless peepers to good effect with aggressive chickens, but currently, I'm noticing that these tiny devices can actually calm a flighty and nervous hen. It's got me thinking that some of our chickens may have a disorder similar to autism in humans where they experience sensory overload. Being neuro divergent myself, I can tell you this sensory overload causes a response not unlike being physically assaulted. This response can look like aggression.
Violet is such a hen. She's nervous, flighty, is constantly pecking at the other chickens, and running away from me when I make any move in her direction. After installing the peepers on her, she has been a different chicken. Peepers remove everything from her vision except for things happening directly upward, downward and to each side with a corresponding reduction of sensory stimuli. She's been calm, relaxed, and seems so much more content. She doesn't try frantically to evade me every time she sees me. She is also leaving the other chickens alone.
I highly recommend giving the peepers a try.