Need to find the workflow definitions that are actually configured to be active? It’s a good way to find configuration bloat that could be cleaned up.

Query for WorkflowDefinition objects and use the ManagementPolicyRule reference attributes that point to the Action and Authorization workflows.

# Find workflow definitions used by enabled Management Policy Rules
Search-Resources -XPath "
        ObjectID = /ManagementPolicyRule[Disabled='false']/ActionWorkflowDefinition 
        ObjectID = /ManagementPolicyRule[Disabled='false']/AuthorizationWorkflowDefinition
    ]" -AttributesToGet DisplayName | Select DisplayName
Filter Validation Workflow for Administrators                     
Filter Validation Workflow for Non-Administrators                 
Group Expiration Notification Workflow                            
Group Validation Workflow                                         
Owner Approval Workflow