Not to be nit picky, but it sounds like you are after a Mollegabet design, not a Holmegaard design. The original Bowyer's Bibles created a LOT of confusion by lumping these two designs together. There are at least a dozen existing bows of the Holmegaard type, and only one limb on one bow shows any step, and that one is minimal. There are two Mollegabet type bows existing, and they both have the pronounced limb to lever transition. Sorry, soap box rant over. No offense intended at all.
As to your question, hickory will work, be sure to keep it dry and heat treat it well. Good luck, there have been many successful bows made of that design. If you are truly interested in a Holmegaard design, then hickory is a fine choice. Again, keep it dry and heat treat the belly.
Kyle