First, in the instance of those born as such:
Immaculata, effeminacy is condemned in the Scriptures. However, there are remedies and it can be minimized. Certainly, if hormonal in origin, the man cannot be held "responsible" for the condition anymore than for the color of his hair.
While, objectively and from a great remove, I might imagine that some of these poor creatures live an agonized life, bereft of real friends and making up for it by gathering any sort of attention they may. In short, even looking, sounding or behaving foolishly matters less than receiving some sort, almost any sort, of attention from others. It might be, for many of them, a terribly lonely existence.
Contrary to socialist dogma, God did not make men equal or even terribly similar. In better times, all men knew implicitly that it was the duty of the strong to protect the person and, as well, the good name of the weak. Whence, the sacred oath of knighthood.
It would seem most un-chivalric to consider that a true knight would mock or terrify some poor soul deficient in his normal attributes, even long before modern hormonal medical advances were developed.
Beyond all that, there are men who cannot enter combat or perform impressive physical feats, from their childhood. They may have any number of other skills of use to society, however, and in which they may justly take pride for their accomplishments.
Now, as to those who adopt such characteristics and behaviors as a result of homosexualism, the matter is altogether different. They may even be chaste but willful in the manner of how they present themselves. It might be an emotional or even an ideological "game" for them wherein they deliberately seek to outrage others. These, I can only suggest, deserve ostracization, full stop. If possible, making it clear that one is neither interested in their views or in social interaction with them must be accomplished or, in some cases, they may seek to raise the emotional stakes and coerce others into "accepting" them, which is impossible.
And that is where the tension is greatest. As E. Michael Jones put it some years back, the queer is now the ideal citizen in fallen America, and Europe as well (save, thank God!, for Russia).
Despite the propaganda, the population of homos is probably less than 2% in most countries. It might be a bit higher in the West today, as a result of immigration from more repressive, non-Western cultures. However, these creatures do not in any way constitute a sizable portion of the population, as much as some of them would like to otherwise convince everyone.
Thus, being polite but distant, prudently avoiding settings where the risk of having to openly deal with an effeminate individual (who probably has any number of new civil procedures at his command if anyone antagonizes him) and, as others said, praying for yourself - first! - and then for his conversion may be, as far as possible, the only practical steps to take.
My remarks are only very general but I hope helpful to you. I have had zero encounters in my lifetime with such people and am trying to pass along what seems reasonable for a Catholic to do. I've seen very few effeminate men and it was always out in a general public setting.
I would hope good manners and being a gentleman or lady would most times carry the day even in an uncomfortable situation.
To close, I've seen quite a number of heterosexual men who were dolts, jerks, creeps and ne'er-do-wells of other descriptions not fit to describe in mixed company. But, they too, and most fortunately, have been a minority.