Specify Anonymous for the Proxy Endpoint Security and Target Endpoint Security.
By doing so the input request will be the plain EAM soap request as shown here. This request you will provide in the input xml section of ION Connection point and ION workflow.
You can use JsonTransformations as the endpoint policies in the header of the soap request xml. This is applicable only for on-premise version of EAM where we are using "Non-Infor" suite of ION API
The sample JsonTransformation is attached to this PDF in the Attachments pane.