
Hi @Mark MacGregor ,
1.You might try SharePoint Migration Tool. The SharePoint Migration Tool is a free tool from Microsoft that lets you move files from a variety of different storage platforms to SharePoint. It can handle large numbers of files and can preserve your file organization.
2.You could use the Konqueror browser to log in to Sharepoint for Linux websites using cookies and WebDAV.
Here's a discussion of automatically syncing shared documents from SharePoint for your reference: Mount SharePoint Online (Office 365) in Linux
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