1)Export articles you want to import with all version from the list view as XML

2) Go to the instance and navigate to articles list view

3)On the number field in list header right click

4)You will find option to Import

5)Select the XML file

6)Click on Import

7)Verify if all articles are imported

Note: As you might know ,If you dont have admin access in the instance you want to import you will not see import option