I have dealt with that exact same issue. You will have a different look than those couples where the man is taller than the lady. A good example is Massimo Giorgianni and Alessia Manfredini. They are a same sized couple, and it appears she might be taller than him in heels.
The technique is a little different for girls taller than their partner or who are same sized as their partner in heels. It can be done, but it is much harder than if the man is taller than the lady. But it is possible with a coach who knows what she/he is doing. The point of contact will be quite different than if you were dancing with a taller man.
Unfortunately, judges do not really like a same-sized partnership or one with a taller lady. We've learned this from experience. "The Look" is a tall, very thin man with slopey shoulders and a long neck, coupled with a tiny, petite lady who has no hips. That seems to be the easiest type of couple to teach as well. At the last few competitions we attended, all the finalists had those traits and body types.
We've been in competitions where we have danced better than those couples in which the man is taller and the lady shorter, yet those couples are always placed ahead of us or put in finals ahead of us. It is very discouraging, but I'm not about to divorce my partner merely because we aren't the perfect size for ballroom dancing.
We know of one couple in which the woman was almost the same size as the husband. He dumped her for a woman who is 4'11" in heels, and this guy is about 5'!0". He gets into finals all the time with this short woman. Sad how he dumps his wife for a midget so he can win or make finals. Not worth it in my book.
