Yes, eyebrow transplants should be implanted at such an angle that the growth lays flat against the face. This is how brow hair grows naturally on most people. If you find that the follicles of your transplant are growing in an unnatural or unsatisfactory angle/direction, they may need to be removed and re-done. I advise you to follow up with your surgeon.
Web reference: http://www.dermhairclinic.com/eyebrow-transplant/