Hi @TKruijer,
When you create a tracking link in HubSpot (Create tracking URLs), and create a QR code for that tracking link, you can later identify the contacts who clicked the link - permitting that they accept cookies in their browser and submit a form on that same or another page.
Without a form submission, this gets a lot more complicated and would require an approach where each contact gets a different link that tracks when it’s being accessed - and thus a different QR code per contact. You would need a third-party tool to create QR codes in bulk.
Best regards