Hi all first post, I have just brought my wife a Byron blue sup it is 8'10"& 32" wide my wife is 5' tall and weighs about 55kgs, is it to short for her. We only paddle on flat water no waves.
Short answer - No.
At that height and weight she should be fine on that board. Like anything, it may take a bit of getting used to, but it really should be fine.