@JaxVent Get her pepper spray and teach her to talk in a gruff voice and to command that if they have no other business where they are standing, then they're going to need to leave her alone.
That may sound weird and stupid, but I can personally attest that it has worked for me. They'll assume that she's either butch or trans and will realize that she's not what they're looking for. If she treats them as if she has a loaded gun in her pocket, they'll back off.
Another thing that has worked for me is keeping pepper spray attached to a keychain in my pocket. When a man gives me trouble, I pull that out but let it hang down at my side. It's a passive-aggressive threat that works. They back off and start being super nice to me, then walk away.
Sad that they're only respectful toward toughness and weapons, and have no respect for women just being our real selves. That is reality though, and your daughter needs to understand that much. Toughen her up early. It'll save her life.