In 801, Louis the Pious conquered the city of Barcelona and during the following decade some attempts to reach the Saracen cities of Zaragoza and Valencia were made, but finally there was not a large scale campaign like the Italian of 773, because the circumstances did not favour it.
Assuming that the circumstances would have allowed a large scale campaign in Eastern Spain and Charlemagne manages to conquer most of Hispania (maybe also puppetizing the weak Kingdom of Asturias), crushing the Saracen hegemony in the Iberian peninsula, which consequences would have had the incorporation of 'Gothia' in the Carolingian Empire after the death of Charlemagne?