I could not find the Task Delegation option.
Nintex Workflow for Office 365
Nintex Forms for Office 365
Using SharePoint Designer I could create a task and the workflow creates a task, which has an option to “Reassign Task” (Delegate).
But this is missing in Nintex Workflow.
Screenshot for more details:
Nintex Task process – Missing “Reassign Task” (Delegate).
SharePoint Designer Workflow:
Clicking the “Reassign Task” button will show the Reassign form.