being an avid cyclist for many years, I can tell you that no, you do not want any ankle support. The reason being that on top of the up and down movement of the circular pedal stroke, the foot also moves side to side in a natural pedaling motion, especially when sprinting and hammering out of the saddle, as when you do uphills.
Adding a brace around the ankle would hinder the lateral movement, thus restricting the performance of the cyclist.
Also, if you look at almost every cycling shoe design out there, they all leave the ankle free to move.