Hi Stefan,
Thank you for reaching out to the API support team, and apologies for the delayed response.
At the moment we don't have an option for a direct integration between our API and the Looker Studio.
If you wish you can prepare scripts on your end, that will query in return reports via the API interface. More about reporting you can read
here.
The whole list of available macros that you can use in your campaigns is available to you
here.
In case of additional questions, please reach out.
Best regards,
Aleš