The Savant Core Technology (FoH p.125) states that the skill must be chosen when this Technology is chosen. What if you use Amorphous? (FoH p.127) Can it change each time since it's added ad-hoc? What if you choose it later as a permanent part of your demonic form? Can you chose a different skill?
The Amorphous Process allows you to switch out one Technology for another. The Savant Core Technology gives you access to a skill at the five-dot level. The question is whether or not you view swapping Savant Core in a different skill is swapping a Technology to a different Technology.
If the StoryTeller would permit a player character to choose Savant Core twice for two different skills, there's no reason not to allow a player to switch skills as a change of Technology.
This isn't overpowered because the player is expending their choice of Process on this ability, and Processes are very powerful Form abilities. A Process should be very powerful. In addition, switching skills would take Aether, and (oddly) if the player switches from skill A to skill B, to switch to skill C they have to return to skill A first, expending more Aether.