You can view all of your trade partners' task assignments across multiple projects with the Task Manager or with the All Tasks Report.
Open the Task Manager from the top menu bar.
Use the "Filter & Search" button to filter among your various projects, assignees, task types, and date ranges. You can even color code the results by trade partner to give you an easy way to identify the various assignments on the List, Calendar, or Gantt Views of the Task Manager.
To color code by trade partners, you will need to have each trade partner assigned to a color on your Trade Partner list (Contacts > Trade Partners).
All Tasks Report
If you go to Reports > All Tasks and then select "Run Report," you will get a report of all of your task assignments, broken down by assignee.
You can run the All Tasks Report just for a particular assignee or across multiple or all trade partners.