Hi €ash!
There is no single way for any two people to have sex, and regardless of whatever body you have, the sex you
will be able to have and enjoy will always be unique to you and whoever the other person is, and it'll always require communication and experimentation to find out what works between you.
So while being trans
is part of your experience, I think part of not knowing what sex will look between you and future partners is pretty universal... Folks with a more cis & hetero experience, might
assume that they know what to expect but inevitably when it comes to the real deal they too will still have to work it out, just like you.
I think it's absolutely fine to fantasize about scissoring, which generally involves rubbing genitals together, which many people find stimulating - so why not fantasize about it? Also I don't think you need to feel awkward about having whatever body you
want to imagine having during a fantasy!
In terms of having sexual intercourse, there is also the option of using toys including strap-ons, meaning that having a penis isn't the only way to experience many of the same things.
So I would perhaps start by reminding yourself that you don't need anyone's permission to have a fantasy, or getting creative. Fantasy is personal and private to you.
This isn't exactly about having sex but have you read any of our
Trans Summer School series? That could be a great place to start if you haven't already!
Also just to show how creative you can get with partnered sex, perhaps take a look at this:
DIY Sex Toys: The Partnered Edition