Hi there, welcome to BYC!
According to how you describe her behavior and laying she is indeed NOT likely sick despite that bare cheek also not being completely normal.
She could have had something stuck in her muff (dried mash) and other birds preened it out a bit too much. Or she might have been bullied. It's always good to do a vent check after dark and look for parasites with a flashlight or head lamp, as that's the easiest time to see them. Since her skin there doesn't look angry or red, I'm not thinking they are related to this instance specifically.
I'm sure many folks will be quick to call your lady an Easter Egger also known as EE on here.
They are lovely birds and some of my favorites and meant to represent true Ameraucana though don't quite conform to the standard of perfection.
There does come a time in every chickens life when they will lose some of their feathers and replace them. That is often around their second fall or 18-ish months but sometimes they don't follow what we think of as "usual". Some some may molt earlier or later. Most do not lay eggs during that time and are often withdrawn a little and ragged as it can be a tough time for them.
Please note.. those feathers on her cheeks do look broken and not like pin feathers coming in. Broken feathers will not usually grow back until molt. Sometimes pulled feathers will sooner but not always.
Adding your general location can help folks make their best suggestions possible at a glance as it helps to gather info that could be useful like your weather conditions, available farm store chains, etc.. things key to helping poultry related questions.
ETA: Does that cheek look normal or like it has any type of abscess? If normal, no worries!
