Archive Emails in one Go

A solution of that sort would also be helpful when implementing M-Files at new customers where new users may have bulk loads of emails in their PST folders and would like to save them all in M-Files with minimal efforts in terms of adding metadata manually.

Exactly, and its a risk management mitigation task as well. This way we could safely store emails, for others to use and access, until a defined date and then make a decision on archival, or permanent deletion.

Still...I have no idea how to do this practically, and whether this is how the system should really be used, versus whether is contributes to bigger problems in the future. I am looking for someone with a strategic/holistic mindset to advise on this, and look at the situation from an Organizational perspective. Is this practical and achievable or is there another way we have not considered.

You could create a external folder connection in M-Files, then mark all Items in your Outlook folder and copy/paste them into the folder which is connected to M-Files.. Not the most elegant way, but should work.. Didn't try though if you can copy thousands of mails out of Outlook in one go..

Edit:

Okay, tried, 1923 Mails copied in around 5 minutes into a local folder..