That's not what QR codes are for, nor is it how document management systems work.

Yes, it is possible, but it depends on how much development you want to do. Do you want a custom button that does this on the form within Sage? Do you want an external application? That is the tricky part. The next tricky part is how you upload it to the document management system you have in mind. The easy part is generating the QR Code. That's as simple as creating a custom URL. If you do that in code, you can copy the response stream and store it in a PNG file or something.

An example of the QR Code is: Custom QR Code