I asked one of our Developer staff about this - his response:
I know you can create a context menu:
http://pro.arcgis.com/en/pro-app/sdk/api-reference/#topic10135.html
You cany use an updatemodule to modify an existing menu, but I’m unsure if they are categorized.
Dynamic Menus can be used to populate a menu with commands on the fly:
<dynamicMenu caption="Acme Menu"
className="DynoMenu"
id="acme_dynoMenu"
largeImage="pack://application:,,,/ProTestApp;component/Images/MenuImage32.png"
smallImage="pack://application:,,,/ProTestApp;component/Images/MenuImage16.png" >
<tooltip heading="Heading" image="pack://application:,,,/Acme;component/Images/MenuImage16.png">Some text</tooltip>
</dynamicMenu>
http://pro.arcgis.com/en/pro-app/sdk/api-reference/#topic10440.html
Those are cool if you want to build a context menu and dynamically specify what it holds based on the context (you could add different tools depending on whether you click on a point geometry vs a polygon, for example). That’s a pretty cool option. J
Hope this helps.
Robert LeClair
Esri-Denver