Is she making that choking motion all the time or only when she's eating?
I've had a few that eat to quickly and end up coughing and sneezing like that.
Looks like she's chocking after gobbling feed.
Do they always have feed available?
Looks they all are diving in.
Same bird as here?:
https://www.backyardchickens.com/threads/what-is-wrong-with-my-silver-laced-wyandotte.1452937/