Nerona Imu

Saint Nerona Imu was one of the twenty kings who founded the World Government after the Voíd Century. He's theorized to be the true identity of Imu.

Abilities and Powers
As one of the twenty founders of the World Government, Imu could rule the World alongside the other families.

Egghead Arc
After Sabo finished explaining what happened during the Levely, Emporio Ivankov theorizes that the mysterious Imu who rules over the World Government in secret is Nerona Imu, who could've been given eternal life by a previous user of the Ope Ope no Mi.