What is an Annotation Group?
An Annotation Group is a collection of Annotation Definitions. The Manage Annotations dialog below lists the Group Name in the red box. Underneath, it lists all of the definitions contained in that group (examples in green). The OpenRoads Standards on the left contains all of the groups and definitions defined in the dgn or dgnlib.
An Annotation Group can be assigned to a Feature Symbology.
A Feature Symbology can be assigned to a Feature Definition.
For example, when an alignment is assigned to a specific Feature Definition, it will annotate according to the Annotation Definitions contained in the Annotation Group. This annotation will display using the OpenRoads Modeling > Drawing Product > Annotations > Element Annotation command. There are several Annotation Groups already established when using a delivered workspace stored in a dgnlib, such as Feature Definitions Imperial.dgnlib stored in the Imperial Standards Workspace.
More information on editing standards can be found here: https://communities.bentley.com/products/road___site_design/w/road_and_site_design__wiki/36316/what-is-the-difference-between-libraries-and-dgn-default-under-the-openroads-standards-in-the-explorer-window.