Use Attach File(s) to attach a file or files from previously collected Items. Files with Workflow Automations cannot be pushed, they can only be pulled. That means that the destination item does the work.
Note: These files must be uploaded to the Podio item directly and not externally on Dropbox, Google Drive, etc.
For example, Workflow Automations is a great tool for archiving Items from App A to App B. When creating an Archive App, be sure to include a Relationship field to the Original App.
First, create a flow to make a copy of the Item in App A
Next, create a flow to collect the files from the old Item in App A to the new Item in App B
You can take this a step further and choose to delete the original Item in App A since the Archive has now been created.
First, add another Status option to App A and call is 'Ready for Deletion', then do a Refresh from Podio in your Workflow Automations account.
Finally, create a flow to delete the original Item.