I've been using AWS AppConfig for a while now and can confirm that the environments capability is not very useful, due to the inability in the AWS console to easily see which version of configs/features are actively deployed to which environment when modifying the active configs/features for an environment.

The AppConfig "engine" separation of configs/features per environment is sound, but the AWS Console lets you down (a fairly common theme).

In the absence of the above usability improvement, we just create lots of "applications" instead (using a suffix, one per environment) and just have a single environment "default" under the application. Modifying the active configs/features then becomes straightforward.

AWS (if you're listening) you need to have a "select" on the config profile page to optionally filter versions by environment, defaulting to the most recent version for the environment selected, and defaulting the "Start deployment" to any selected environment.