You can use VeloPro workouts on Zwift.  In order to do this, you must convert the workout to and "indoor" workout and then send the .ZWO file to your Zwift instance.

To do this, from the Training Plan tab on your Dashboard, simply click on the white space below the workout you want to change to indoor.  This will open a dialog box with an option for "Indoor/Trainer Workout."  Choose this and VeloPro will convert the workout.  Then, simply click on the workout to download it as an ERG or ZWO file.