Unironically there's a fair few incidents where someone being crowned queen of love and beauty was not done for romantic reasons so in theory you could get away with people not getting it
I am sure that it would have been pretty common for an unmarried knight (or a knight whose wife was not in the tourney) to crown a woman related to him (his sister, niece, cousin, or even mother), and no one would be particularly bothered...
Then the Targaryen came with their "Queer Customs" and you couldn't do it without getting weird looks and whispers behind your back
...
Plus it helps that unlike a man doing it, I guess, Rhaenyra can't exactly crown a man without it coming off as mocking/emasculating to them; unless the man was like, her husband and everyone knew them to have an easy-going relationship.
Hey, since a good portion of the Valyrian Blooded boys are so lithe and androgynous, there is a decent chance that someone crowned a boy Queen of Love and Beauty because he thought he was his sister
...
I mean, clearly it would be emasculating to crown our husband the queen of love and beauty. We can't do that. So we'll just have to keep crowning our dear companion.
So, Alicent it's the only option, really. Pinky promise.
Well, if Johanna's genes have something to say, we are going to have quite a few sisters that we may crown without being that weird or problematic...
That would also be weird and problematic, but for totally different and funnier reasons...
Gwayne: He at least knows about Alicent's feelings for us and didn't seem judgemental about it. He might not be willing to be a beard though - maybe he has similar romantic notions. This would go a long way towards making the gf's dad happy. Also, she's the daughter of a second son - it seems at least plausible he'd begrudgingly accept her being a "confirmed bachelorette" if he gets grandkids on the throne.
I want to point out that the gulf between "I know my sister is a lesbian but love her and I don't care as long as she is safe and happy" and "I know my sister is a lesbian, and I am willing to marry her lover to be their beard" is pretty damm massive...
Harwin: I think this is the iffy-ist one relationship-wise. He had an extramarital affair in canon, so it might be presumed he wouldn't care about us having one on him… but Rhaenyra was probably not actually having sex with Laenor that much (maybe at all) over the course of their relationship. Also might lead to relationship drama, since he is a romance option in his own right.
Well, I think that from what series canon shows, we can deduce that there is a good chance that Herwin wouldn't be against sharing Rhaenyra with Alicent, and besides that, I consider that him being a romance option in his own right is a plus...
The other male romance option that I am pretty certain that wouldn't be against a poly relationship is Qoren Martell, since for what we have seen with Dornish nobility, poly relationships are pretty common there, and honestly bringing Dorne into the fold 100 years before canon and without wasting the lives of 60000 men sounds pretty great.
The easiest way to secure Alicents future would be to grant her a small estate for her long years of companionship, advice and aid rendered to us.
Perfectly normal thing to do for a monarch.
And after a civil war, there will be a lot of free small states that we have taken from traitors that we will give to our loyalists, family, and friends...
So we just have to keep one of the nicest ones in reserve for Alicent...