I've always found both to be attractive, but in different ways.
Guys are not primarily about the visuals to me, but about if they are kind, intelligent, brave, etc, and I've always been very interested in them romantically, once I actually started feeling these things at all, which was in my mid 20s.
Meanwhile, in a different part of my brain, I also find the female form attractive, but I think a lot of it is admiration, and protectiveness. Nothing romantic.
Have you kissed both? I think that's a great indicator. I feel nothing kissing a girl, but I feel euphoric kissing a guy, or late-transitioning trans-female.
And I think that kind of upsets or offends most trans-women, knowing that part of my attraction to them is their masculinity, because most of them vigorously reject and conceal their masculinity. And I'm mtf transgender myself. I'm just not very good at it, apparently 