Impossible to connect to Salesforce Marketing Cloud

[emailing-ppl]

Hello,
We are a company using Salesforce Marketing Cloud. It's said in the plugin description that it can connect to Marketing Cloud but we are unable to perform that.

We are using Marketing Cloud as a SAAS hosted by Salesforce. We are not using the Salesforce Platform force.com . For this reason the Marketing Cloud web app is hosted on a Salesforce end point : https://mc.s10.exacttarget.com/.

How can we setup the plugin so we can access the Salesforce Marketing Cloud API ? The API endpoint is https://mc1k6[...]hwf17s4.auth.marketingcloudapis.com/

Thank you very much for your help !