It depends on what you mean by flattering. If you want to emphasise a feminine figure, then that's always going to be sexy I'm afraid, so you'll probably want a different approach for deflecting male attention. You can, however, get well-fitted jackets, shirts etc in good materials that don't cinch in at the waist, and trousers cut straight to deemphasise the rear if you merely wanted good quality clothes. Look for the androgynous style fashions from the last couple of years.