Searches regarding post female transition like the one you see below are a common search:
Take the German pole vaulter Yvonne Buschbaum, she was a very fit and athletic woman before testosterone:
Susan buck angel Lee:
(at one point) or average. None the less, even the more naturally narrow and athletic hipped seen here before transition, STILL possess obvious womanly (curvy) shapes after. Exercise can help disguise the natural hour glass female figure, and clothes too go a long way to hide curvaceousness. But if you cannot reckon that transition in and of itself will NOT remove your female hips/shape, then you might want to do some serious therapy to address this discomfort BEFORE you transition. And if you have transitioned already and the masculinizing effects of synthetic hormones and surgeries only go to emphasize your feminine attributes, increasing them even. Or for some, the first time developing dysphoria, you will need to come to terms with being a woman even if you are passing as a man, if you wish to truly be at peace with yourself.