Well, from a traditional perspective, I don't think there is any homosexual agenda is hidden here, it could be just another prank between two cousins and what you need to notice is, Phoebe falls in love with the "disguise"( disguise of a man) , not with the "person". But if you want to put the text in a larger structure considering all the biographical elements of Shakespeare and also mix a bit of queer theory, well!! then the answer is yes! Arguably Shakespeare was a homosexual who dedicated 126 sonnets to a young man describing his physical beauty; to be specific and only 25 sonnets to a dark lady expressing direct or indirect hatred. And as you know literature goes by reading between the lines, so I think, putting two sisters in his own shoes and attempting a sex-role reversal is not much irrelevant for Shakespeare. So in that sense you can say that he supported lesbian sexuality.
