You can see a demonstration of the Office Module in the Property Editors and Reports sections of the Feature Center demo installed in the %PUBLIC%\Documents\DevExpress Demos 19.2\Components\eXpressApp Framework\FeatureCenter folder.
Office Module Capabilities
Rich Text Editor
The Office Module provides two platform-specific Property Editors:
the RichTextPropertyEditor, which uses the RichEditControl in WinForms applications
the ASPxRichTextPropertyEditor, which uses the ASPxRichEdit control in ASP.NET applications