Well, Italy had worked for at least a decade to have the ok from the other powers to go after Lybia, suddenly change objective will be very difficult both in the internal front and on the international one; the only way that i can see happening without a PoD at least a decade earlier is that some big internal problem in Ethiopia expand in the italian colonies and a military solution is approved to at least stabilize the situation (aka getting a better border to defend...as minimal objective and putting a more friendlier goverment in charge as best solution, but both also mean getting the ok of France and UK due to previous treaties).
While i doubt that will be something like the 1936 one and more probably a more limited operation, can go better of OTL lybia due to at least knowing better the situation and having more limited objective.