I am working on a robotics simulation application in Unity. I want to replace the default physics engine, PhysX, with Mujoco. My goal is to enable a toggle within the Unity application to switch between using PhysX and Mujoco. Mujoco prives better realism for certail scenarios, but i also want to leverage Unit's default capabilities for simpler tasks.

Currently, I am new to Unity and have limited experience, so I would appreciate guidance on the following:

1. What fundamental concepts or features of Unity and Mujoco should I learn to address this problem effectively?
2. Are there any tutorials, documentation, or examples that demonstrate replacing Unity's physics engine with Mujoco?
3. Do I need to duplicate assets, scenes, or environments to implement both physics engines, or is there a more efficient approach?

Any advice, resources, or pointers would be greatly appreciated!