I would double up and do cardio + strength training. In strength training I would work on upper body and in cardio, work on the core throughout (keep the core in tension) and push it to fat burning levels. Throw some power squats and gluts work in there. I'd aim to even everything out and so the cardio is to lose fat while also adding in some exercise to strengthen the abs (to make the abdominal area wider with muscle) and gluts (to build them up a little) and it would give a straighter shape. Planks will help strengthen core too. If you were to work on gaining muscle and losing fat I think it would be your best bet. While T does cause redistribution of fat, it's way more focused on storing new fat in new place than it is taking fat from old place and moving it. So I'd suggest trying to lose that fat accumulated when internally female and then, all going well, the fat should then gather in the abdominal region instead where you'd gain a more masculine figure. If this doesn't happen for whatever reason, you'll need to talk to your doc about T levels.
Remember, if you're going into training that you have to up your calorie intake and work on getting a decent amount of protein each day to help with muscle development and recovery, best case scenario: pre, during and post workout drinks/shakes. You want to balance this out, not get skinnier. What you lose in fat, you want to gain, and some, in muscle. It's actually impossible, with exercise alone, to target which fat to lose. You just have to work to lose fat in general and it should come off your hips slowly but surely. However, you CAN target muscle development so doing this at the same time to take focus away from hips will help in long run.
You were born female, so no matter what you do, you will always have a wider pelvic girdle than cis men. However, with some muscle building as well as picking the right clothes, you can hide it to the point where you'd never notice. Your hips will likely always have a curve to them, and more so if you stay skinny. Bulking up a little in the thighs > shoulder region will help flatten it out a bit though. If you have more of a small build, like it sounds, you wouldn't even need to bulk up much.
And something else to note. I do an at home workout where this guy leads the workout:
http://1.bp.blogspot.com/_4XlXIgOBFjw/TLEaSO9ny7I/AAAAAAAAAZg/LFMDqlALQYU/s1600/DSC_0043.jpgWhat I notice watching him (especially when he shows exercises from the side) is that he actually has a little bit of a curvy look. I'd even say he looks more curvy in the hips than the girl next to him. But what evens it out and makes it a more masculine curvy figure is with or without the shirt, he's in proportion. The shoulders and arms come into a straighter figure that seems to curve out a little, but he has a muscular butt and quads, so it all looks in proportion and it looks right that there should be a little curve there - and you can use that feature to your benefit!
Good luck!
