How can I create selection sets based on profiles? (a series of selection sets containing the elements within each profile)
As of May 2020, this is being considered for a future version - reference Enhancement # 321992 (storm/sewer products) and 322526 (water products).
Workaround:SewerGEMS, CivilStorm, StormCAD, SewerCAD
As a workaround, if you are using one of the storm or sewer products and the profiles were created using the Auto Create Profiles feature described here (one for each branch of the system), then you could potentially use the Branch Labeling feature (Tools > Tools > More > Branch Labeling) to label the branches, then use a series of queries to select the elements of a branch, right click in the drawing > Create selection set. If your goal is to export the data, you could then export your element flextables to Shapefile or CSV format.
If you are looking to create selection sets in order to manipulate a flextable and present the hydraulic data associated with each profile, consider using the Profile Annotation Table, which is customizable in Engineering Profiles, as seen in this article: Ability to customize profile annotation tables
Workaround: WaterCAD, WaterGEMS, HAMMER
In the Water products, a possible workaround could be to use a predefined query if possible, to select the elements in the same way that the profile was created. For example if you have a profile that follows the shortest path between two particular elements, you could use the "Find shortest path" query. This is found under View > Queries > Queries-predefined > Network Trace > Find Shortest Path. Select the start and end nodes and run the query to select the elements between.