At this county fair, what category do they have for her? If Ameraucana, she would be disqualified, though many county fairs are much more lax/casual with their categories and judging.
Many hatcheries sell EE as 'Americanas, Ameraucanas', but in reality they are crossbred chickens carrying the blue/green egg laying gene. Trust speckledhen and me. She does not meet the breed specifications for any of the Ameraucana varieties. Sorry, but that is a fact.
No, Ameraucanas do not have green legs. They have slate legs. She is definitely what the hatcheries sell as Ameraucana (incorrectly sometimes spelled Americana) or even worse, the more rare Araucana, neither of which they do sell, but she is an Easter Egger pullet.