Batch Replacing Files on eB

Hello,

We have many files that need to be replaced within records on eB Director Version 15.5.1.236.  Could someone please explain how to batch replace these?

What we have been doing is downloading the files to a Windows File Explorer folder from eB Web through "Get All Files", making changes to those files (basically just inverting the image), and then replacing the files within their corresponding records in eB Director individually.

If there was a way to do this in bulk it would be really helpful.  Thank you in advance!