You can export and import workflow templates by changing the state back to a workflow and after importing the workflow you can change it back to a template. Since this is not the desired approach you can vote on a product suggestion on Connect which asks
for functionality to export and import workflow templates:
https://connect.microsoft.com/dynamicssuggestions/feedback/details/565467/export-and-import-workflow-templates
Ronald Lemmen
Microsoft Dynamics CRM MVP
http://www.ronaldlemmen.com