-Standalone Provider & Settings asset does not show in AdaptivePerformanceGeneralSettings asset.
-Workaround: Enable "Device Simulator Provider" in Project settings.

Steps to repro:
1. Create a new project.
2. Edit > Project Settings > Adaptive Performance > Install.
3. Project > Select AdaptivePerformanceGeneralSettings.

Actual Result:
Standalone Provider & Settings asset does not show in AdaptivePerformanceGeneralSettings

Expected Result:
Standalone Provider & Settings assets are showing in AdaptivePerformanceGeneralSettings

Reproducible in:
2020.2.0a15, 2020.1.0b13, 2020.1.0a11 with Package Version 2.0.0-preview.8.

Note: Adaptive Performance and simulator option is not available in Project settings with Package Version 2.0.0-preview.4.

Environment:
Occurring on Windows 10 & Mac 10.15.