You might want to move or copy files from one SharePoint location to another. This is a built-in funtion, so no third-party tool required.
There are limitions. Microsoft documents these limitations:
Moving and copying across sites
Copying/Moving multiple files in a single operation has three requirements:
- No more than 100 GB total file size
- No more than 30,000 files
- Each file must be less than 15 GB
According to Microsoft, not only would Mover.io likely incur the same errors, but the workaround is to use the OneDrive sync app instead. Evidently, the OneDrive sync app will overcome the file structure and document type issues. So, just fully sync all of your file/folders to a Windows machine, open two File Explorer windows side-by-side, and then drag and drop.