Thought the same, from her charachter's developement it doesn't seem like Yuzu would ever wear her hair in a style that gave her such a harsh look.
Sabu rarely uses a female character design with a hairdo showing the forehead—the mom is the only one I can think of offhand. In fact, quite the contrary—all the main characters have hairstyles with distinctive bangs or fringes that reach to below the eyebrows.
So maybe she’s just not used to drawing foreheads, which does raise that question of why have Yuzu feature her bruise without mentioning anything about it? In terms of plot there’s no reason to show the bruise to everyone, and would her bangs really cause enough discomfort for Yuzu to change her hairstyle so radically?
Just seems a little odd because, for all the big and little inconsistencies of plot and characterization, visual character design has generally been the most rock solid aspect of the series.