Note: Differences in Permission Management for Document Sharing between Personal OneDrive and Office 365, and across Windows/Mac

To summarize the results of my verification:

• Sharing a reasonable amount of documentation over the long term
• Sharing among multiple people with team turnover
• Sometimes needing to invite guests
• Wanting to synchronize with the local file system, not just operate via a web browser
• Wanting to use it on both Windows and Mac

In this scenario, it is currently quite difficult unless all users have an Office 365 account.

Details are below.

Personal OneDrive

• Synchronization with the local file system is possible on both Windows and Mac by installing the OneDrive app.
• Files and folders can be shared individually.
• Shared folders can also be synchronized to the local file system. See here
• Sharing is done via URL, and anyone who knows the URL can access it.
• However, the owner can see who has accessed it, and can revoke or change access permissions per account.
• Note that this is reactive (post-access).

Since it is for personal use, there is no concept of an organization, and it can be shared with anyone.
However, because it is for personal use, a drawback is the lack of granular access control when sharing.

Office 365 SharePoint Document Library

• For Office 365 account holders, synchronization with the local file system is possible on both Windows and Mac by installing the OneDrive app.
• Sharing can be finely controlled and can be shared with guests outside the organization (if permitted by the Office 365 administrator!)
• However, on both Windows and Mac, even if invited as a guest, you cannot synchronize with the local file system unless you are already in a state where OneDrive is synced with an Office 365 account.
• Using it via the web is fine.

It is unfortunate that even though you can invite someone as a guest even if they are not an Office 365 user, if the invited person has a Microsoft account (not an Office 365 account) and is syncing with OneDrive, they still can only access Office 365 resources via the web.