The clubs are discussing the final details for Idrissi, 24, who will join Sevilla for €12m plus €3m in variables.
Idrissi was one of the best players in the Eredivisie last season, scoring 17 and assisting 10 goals in all competitions.
Idrissi will add further depth to Julen Lopetegui’s squad, providing competition for wingers such as Lucas Ocampos and Suso.
Born in the Netherlands, Idrissi decided to represent Morocco at international level and has won seven caps.
He mainly plays as a left winger but is also capable of playing on the right flank.