I’ve searched and i cant find any way to do this.!
I think that is a great help for development if there is an option on 1 or more Blueprints named “Extract Parent Blueprint” that allow to select which variables and components you want to extract for Parent Blueprint, makes a new Blueprint with selected variables and components, remove the selected variables and components from the existing Blueprint(s) and assign to the existing Blueprints’ Parent Class the new Blueprint.