How to Move a folder from one datasource to another datasource using powershell
You will not be able to move directly from one datasource to another, your best bet is to open one connection and use Export-PWDocuments to a local folder and then upload to new datasource from it
And if you need to move it with security, audit trail etc look into the Export-PWDocumentsToArchive and Export-PWAccessControlToExcel on the source datasource. When you get to the destination look at the reverse, Import-PWDocumentsFromArchive, Import-PWAccessControlFromExcel. these 4 options are incredibly powerful. If you use make sure security matches up on both datasources, user list names etc, whatever you use. Look at the exported excel file before you import and you will quickly know why. Good luck.