In 1821, the last viceroy of New Spain, Juan de O'Donojú and the comander in chief of the victorious "Trigarante" army, Agustín de Iturbide signed in the city of Córdoba, near Veracruz, a treaty that recognised the independence of México and estabilshed that the mexican crown would be offered to Fernando VII, king of Spain or, if he refused, to another member of the spanish royal family, forming some short of hispanic Commonwealth.
But the spanish consitutional Cortes, lead by the ideas of people like Flórez Estrada and other strong centralists (in the imperial affairs, strangely not in metropolitan affairs) refused the treaty, leading to the complete break of ties between Spain and México (and the proclamation of Iturbide as emperor) .
So, what if the Cortes accept the treaty? Could that boost other monarchist-autonomist movements in the colapsed Hispanic Imperial System? My guess is that it could have a replica in the vicerroyalty of Perú and, maybe, later in Flores' Ecuador, but I have doubts about Río de la Plata and Nueva Granada. How the international relations change? Could it last or the internal tensions in Spain and the Americas break away the new order?
Cheers.