You can change which features are included as part of an analysis library feature in the library feature part or assembly document (*.sldalprt and *.sldalasm respectively).
You can edit an existing library feature and save it with a new name (and extension) to create additional, similar library features.
After the library feature is inserted into a part or an assembly document, you can edit a library feature using the same techniques that you would use to edit any load, fixture, or connection.
To add or remove an analysis library feature:
Right-click the feature to add, and select Add to Library Feature or Remove From Library.