How do you interpret the passage from Plutarch then? It seems clear that the bride dresses male because the groom is more used to male sex.
His info is also disjointed as he claimed to have put them to together from various sources. For example in the passage about the marriage rites he talks about how Spartan men didn't see their wives in daylight before they became fathers, While in the passages before he talks about boys and girls partying and singing in the nude with the girls praises and mock their accomplishments and how the female nudity is there expressively to facility marriage. Given that the Spartiates numbered in the 3-4000 so the boys that went entered their 20thies would have been in the hundreds and marriage prospects was further regulated by wealth and status, Meaning that any Spartan's would know well which handful of individual they could end up marrying from early childhood.
I find this idea that that the bride would dress as a boy as to make the men more comfortable with heterosexuality hilarious. So these boys that trained from childhood into enduring cold, pain, hunger beaten into obedient competitive super soldiers yet it was when these young men with testosterone out of their eyeballs were compelled into sexing it up with the girls, their sensibilities needed to be spared. The gay conversion therapy must have been perfected in those days.