Plugins

UnityPlugins
Search Extensions - Unity extensions for quick search in project files. Includes something like DependenciesHunter.
Localization - Unity localization package.

Third Party Assets - most of them are industry standards. Zenject - DI container. It is a kind of industry standard that is used in a huge number of projects to work with dependencies.
VContainer- DI container, which, according to the authors, works much faster than Zenject and doesn't contain extra third-party things like Signals (from Zenject).
UniRX - plugin for creating reactive fields. It is most often used to notify the UI about changes in data models.
R3 - improved UniRx.
UniTask - is an industry standard for working with async/await code in Unity.
DOTween - is an industry standard for creating various twin animations, for example in the UI.
PrimeTween - is an analog of DOTween, which, according to the authors, works faster and creates less garbage than DOTween.
AsmdefHelper - generates a dependency graph based on the assemblies existing in the project.
DependenciesHunter - helps to form a dependency diagram within the project, which asset use one or another asset. It can be useful to understand who exactly uses this asset and whether it is needed in the project at all.
Graphy - пplugin for displaying FPS and other build resources.
InGameDebugConsole - debug console for displaying game logs and entering certain commands.

NativePlugins - native plugins for mobile devices with ready-made implementations of functionality.
NativeShare, NativeGallery.