Have la Baltraneja emerge victorious so *Spain is the union of Castille and Portugal rather than Castille and Aragon (no clue what this does to Aragon or Italy, probably means the French get pieces of both IMO). Turning their backs on Europe they avoid the Habsburgs, instead focusing on first North Africa (as OTL but more successful) and then the New World and beyond.
*Spain's capital is probably Seville (or Lisbon for that matter). Absent involvement in Europe I think they can manage most of what both empires did OTL overseas and a bit more besides.
This, IMO, would probably be the best pod for fulfil, if not the whole North Africa as ask by the OP...at least a more Atlantic and African focussed ALT Spain (Portugal plus Castile) and in consequence besides of a bigger and more permanent expansion in Morocco and some of Argelia, at least a delayed discovery of America and of course, if happen... a late and very different type of approach to the discovered lands and its economical or commercial exploitation.
Also Aragón would remain focused on the Mediterranean and in rivalry with Venetia and guess that in alliance with strong alliances with Navarre and France that given the Italian ambitions of the French Kings in TTL (with a different Battle of Toro) would lead to, if not to a full dynastic union within France and Aragon, at least to a marriage alliance between both royal houses.
Anyway, would expect to more Mediterranean focused French politics that would probably back and share the Aragon Mediterranean interest.
Also, this would mean for France (or even for ALT France-Aragon) and this ALT Spain that the OTL Italian wars besides of be affected by the butterflies wouldn't have reason to be fought.
For France this would mean no waste its material and mainly human resources in decades of wars in Italy and against the Habsburg menace of encirclement and wouldn't have any reason to seek and make an alliance with the Ottomans. But in alliance with Aragon to conquest the Barbary enclaves in Argelia, Tunisia fought Barbary or Ottoman corsairs in the Maghreb. But mainly guess that would be against Venice, but guess that mainly against the Ottomans.
This Alt Spain or rather Alt Portugal, given that the Ruler, that would be the Portuguese monarch and the strategic goals would be decided in Lisboa/Sevilla and this would be an Atlantic one, that would mean that would be full focused in strengthens and develop both its foothold in Morocco and increasing its control of the commercial traffic with East Africa, the India and mainly the Spice Islands and the Far East with Europe.
Also in TTL the way to develop and get the economical revenue could be both somewhat different, more spread, but stronger and with bigger resources and better means to reach its goals and for defend them than OTL.
Also this Alt Monarch would have at the Castilian army (and the bigger than Portugal Castilian pool of resources that would help to form a bigger and better army that in OTL (Portugal or Spain).
This would be an army that how was showed in OTL by each one the new joint army would become in one of more strength in Europe and with its leadership and soldiers (that as OTL would be veterans both in the internal/dynastic wars and in the Reconquista wars) could be guess that easily would show again, TTL, because this army was considered as one of better and more capable to adapt and to be strategically innovative and tactically flexible from Europe.
Finally must be taken into account that in TTL this Alt Spain/Portugal besides of a bigger and stronger navy would has a greater population and Economy.