So what is the lesser of two evils here that Portugal can end up with, a Republican victory and maybe it turning into s Soviet puppet state in the future ore a Nationalist victory like OTL ore could we have a third option with a Portuguese involvement in the Spanish civil War with them doing the Royalist route with them trying to restore the monarchy.
That would be a stupid idea.
The best that can be said of Alfonso XIII is that he was a corrupt incompetent and the monarchists are more or less universally reactionary hyperconservatives.
Much easier to try to unfuck the Republic, which is not foreordained to become a sockpuppet of the Supreme Soviet, as long as there is someone around who doesn't furiously backstab Spain the way France and, very particularly, Great Britain did historically.