size limits and other questions
As far as storage limitations in various editions, you can find the feature matrix at the bottom of this page: https://www.cloudberrylab.com/backup/windows.aspx
Regarding copying of data to S3: CloudBerry Backup is a backup product, not a file sync tool. So each file needs to be processed, logged, and moved to the backup storage in our backup format. From that point, you can manage version retention and backups of new versions and new files and restore needed versions when needed. It's not possible to use already uploaded versions of the files in their native formats. But once the backup is complete, you can opt to manually remove the old file copies in S3.
File Sync is not really backup, but if it's what you really need, then another product is probably in order. If you want to describe your particular needs in more detail, we can provide additional guidance.
BTW, it sounds like from your description, backup is what you need, but you'll have to use Ultimate Edition with the data set sizes you have.