From the point of view of Franco? A Fate that is... less than optimal, shall we say? Franco wasn't an idiot with delusions of grandeur & dreams of empire. His army was ill-equipped, his infrastructure was still shattered, and the Spanish people were exhausted from the Civil War. And, even if Gibraltar fell, the British still controlled the seas, Spain would starve. Which is why his demands to Adolf in return for Spain actively joining the Axis were so high. Excessive, even, from the Germans viewpoint. Franco knew exactly what would happen to himself and Spain if he signed up. He also knew that Spain was far more valuable to the Nazis as a neutral.
From the point of view of the Falangists? See above, even though a significant minority would have jumped feet first into a full-blown military alliance, regardless of the consequences. Fanatical Fascists are going to Fascist, after all.
From the point of view of Spain? Even more blood, death, destruction, disease and starvation, followed by occupation and restructuring. Post-war de-fascification and the return of either a more democratic republic or a constitutional monarchy, because there is no way in hell the Allies would permit the Falangists to remain in power. Spain would probably also lose her African enclaves & colonies. The Canary Islands would definitely be occupied by the Allies, especially if Gibraltar was threatened/captured. A post-war independence of Catalan could also be possible.
From the point of view of Portugal? A total shit-storm, with Salazar cursing Franco's entire bloodline with eternal damnation, for forcing Portugal into said shit-storm. Portugal would try to remain neutral, similar to Switzerland, Sweden, etc., although I could see Salazar siding with the Allies AFTER successful landings in Spain made it relatively safe for him to do so. He would be too mindful of what happened in Greece. I can also see Salazar privately agreeing to an Allied occupation of the Azores, while publicly decrying it as treachery to placate the Germans.
From the point of view of poor, little, almost constantly overlooked, Andorra? Probably borrow a leaf from San Marino and pray the oncoming storm doesn't hit them too hard.