As planarchist said, you might want to have a look at the link to the Resale Wizard he provided.
It’s a physical Elicenser with the license on it that the buyer needs to receive, not an activation code. Activation codes are used once to download the license to the USB key. Once used, they have no value.
Also, btw, it’s only the dongle w/license that the buyer needs- the downloads are available to anyone, license or no, via the Steinberg Download Assistant.
I see that the box in your pic says ‘update to latest version included’, but of course you’re aware that that refers to what happens when the activation code is used and the license is downloaded– your buyer won’t get that perk. I mention it because the price of your offer is only 60 USD less than a new Cubase Pro 9.5.