AWS Config support for Amazon SNS is now available in AWS Commercial and AWS GovCloud (US) Regions
AWS Config now supports Amazon Simple Notification Service (Amazon SNS) in all AWS Commercial and AWS GovCloud (US) Regions. AWS Config provides a detailed view of the configuration of AWS resources in your AWS account. This includes how the resources are related to one another and how they were configured in the past so that you can see how the configurations and relationships changed over time.
Source:: Amazon AWS