Hi @canozdemir,
Greetings from McAfee.
We are sorry, but we do not have the option available right now to activate the McAfee subscription using activation key without creating a McAfee account. The McAfee account is created so that our users can manage and view their subscription details and devices for their convenience.
However, we will consider your feedback and share it to our product and engineering team.
For your reference, below is the McAfee article with the steps to activate McAfee subscription.
How to activate a McAfee product subscription with a product card
For further assistance, feel free to reach our McAfee Support
Regards,
Abhi