Yep I agree with her being IB white eyed. How much white a hen has varies quite a bit, from none like her to a "chessboard" of silvery grey and white feathers.
The amount or placement of white feathers can change over the years. It's especially noticeable with yearling hens as they fully mature- some are born with little or no white then have hundreds at 4 yrs. The reverse also happens... a "chessboard" yearling can become rather solid colored at maturity.
Much more reliable are the sugar-frosted look(when she moves around you may notice a whitish cast to the feathers) with or without a greyish color on the peahen's bodies. These are more consistent than white feathers.