When viewing an asset on your feed in SHIFT, users can instantly import the file to any of the workspaces that they have upload permission on.
To use the Import feature, go to your Feed and find select a file to open up your asset details window. When there, click on the cloud with downward arrow icon to open drop down menu. Select "Import" to open the modal.
The menu that will come up will give you three different destination points to choose. Once you decide the workspace, project and folder you want to import the asset into, click Import.
Also - the Import feature is available on at the bottom of an asset's Feed card by clicking the cloud icon.