I'm Irish with friends in Spain, having lived there for one year. I too have been curious about the name Moran in Ireland and Morán in Spain.
We believe the Irish Moran is an anglisization of a few older Irish names.
While in Spain I read in a certain book that the name Morán was Spanish. I would however bear a few things in mind:
1: Alot of Irish went to Spain to fight in the Spanish civil war.
2: Alot of Spanish sailors were shipwrecked here over the years.
3: I remember seeing someplace?? here in Ireland an old family tree putting a Spaniard at the top of the tree.
I have been trying to rack my brains to remember where it was for years because I'm dying to know if Moran from only Spain or Ireland.
What is Moran de Buitron, Grandees of Spain ??.
If I can help in Ireland or Spain please let me know. If you find out anything could you please let me know at firstname.lastname@example.org