I'm trying to think of examples of female-on-male creepiness that I've experienced and heard of, and the only examples I can think of fall into the categories of mere mild-discomfort-induction and outright stalking. Male creepiness appears to have a significant middle ground that seems to be almost completely absent in the other direction.

Perhaps this is related to the disproportionate prevalence of male-on-female rape and sexual harassment — because those are strongly negatively-valued events, it's worth having a sensitive filter that'll give false positives sometimes. But that depends on whether features associated with "creepiness" are less perceived as creepy in women by men or if they are actually less prevalent in women.

Edit: I have a friend who's internet-famous-in-some-circles and he has had a lot of experiences with young female (and a few male) fans who've crossed the line into conventional creepiness but not into stalking (plus a few who have...), but people act differently toward celebrities. Probably doesn't generalize very well at all to interactions between, say, two people meeting in a bar.