The behavior of mounting other hens is typically observed in roosters, but occasionally it can be seen in hens as well. This behavior is related to dominance and can be a way of establishing pecking order within the flock. If your hen is mounting other hens, it could be a sign that she is trying to establish dominance over them. However, if this behavior is excessive or aggressive, it could indicate that there is a problem within the flock and that the birds are not getting along.
As for going broody, some hens are more prone to broodiness than others. Broodiness is a natural instinct for hens, and it occurs when they want to sit on eggs and incubate them. During this time, hens become very protective and may stop laying eggs. If your hen has gone broody multiple times, it could be a sign that she is particularly prone to broodiness.
To manage these behaviors, it's important to ensure that your chickens have adequate space, food, and water, and that there are no underlying issues within the flock that could be causing stress or aggression. If the mounting behavior continues or becomes aggressive, you may need to separate the hens temporarily to prevent fighting. To discourage broodiness, you can also remove eggs from the nest as soon as they are laid or provide your hen with a separate area for brooding with a dummy egg until she loses interest.