This may work for you - it worked for me.

1/ Create a formula that contains the data you want to convert to a QR Code in the following format
"http://api.qrserver.com/v1/create-qr-code/?size=90x90&data="+cStr({Inv.QRCode},0)

Add a picture to the report.

In "format graphic", go to the pictiure tab, and change the formula of the graphic location to the above formula.
e.g.
{QRCodeAsURL}

It's not perfect, and it uses an external web service but it works.