Subsystems provide an easy way to extend engine functionality and implement new features, but there is nothing that could be used to visualize them in editor or allow to adjust their properties on the fly.
The Subsystem Browser Plugin comes to rescue with a dedicated editor panel to display which subsystems are currently active and allows viewing and editing of their properties.
GitHub Source: Here
GitHub Issues: Here
Number of Blueprints: 0
Number of C++ Classes: 18
Network Replicated: No
Supported Development Platforms: Windows, Linux, MacOS
Supported Target Build Platforms: All