Can I host Windows Forms Controls inside a Diagram?

 Yes, Essential® Diagram has a Syncfusion.Windows.Forms.Diagram.ControlNode node class that allows you to host Windows Forms controls inside a diagram. The ControlNode type can serve as a container for almost any type of Windows Forms control and can be used as the child node of a symbol or as a top-level child of the diagram model itself. ControlNodes can be created and activated using the interactive Syncfusion.Windows.Forms.Diagram.ControlNodeTool. Control activation is determined by the ControlNode.ActivateStyle property.

The 'QuickStart\ControlsGalore' sample that ships with Essential® Diagram demonstrates the ControlNode and ControlNodeTool classes.