All of Odin's editor features works without inheriting from any base-class. We've made sure that all of Odin's attributes is in its own .dll file. That way, you can always remove Odin, and only keep the Sirenix.OdinInspector.Attributes.dll and continue with your project, without any compiler errors.
However, as soon as you commit to using Odin's serialization system; leveraging classes such as SerializedMonoBehaviour and SerializedScriptableObject you could be in for quite a ride if you suddenly need to uninstall since you would need to find a replacement for serializing your data or make one yourself.
If you should stumble upon any issues please report it on our issue tracker. We'll do our best to resolve it as quickly as possible.