There isn't a built-in feature, but you can do it in two ways:
- Using an Extender rule triggered by a Data Management with a few parameters. The function BRApi.DataQuality.Process.GetConfirmation(si, yourWorkflowClusterPk, True) will return an object with the relevant properties (cycle through the .Groups property for details of each group). Use BRApi.Workflow.General.GetWorkflowUnitClusterPk to build a clusterPk to pass to that function, identifying the wf instance you're interested in. You can then output the results as csv or any other file format.
I would recommend this approach as the cleanest and likely most robust.
- Using an SQL query. The main table is ConfirmRuleInstances, which you will then have to join up with ConfirmGroup, ConfirmProfile, and WorkflowProfileHierarchy to make it intellegible. This doesn't require coding beyond SQL (you can use a Data Adapter). The adapter could be attached to a Dashboard Grid component, which you can then export. However, JOINs can be tricky to do correctly, and things might break if OneStream changes table layouts in later releases.
By the way, this could be a useful feature to file on IdeaStream.