Is it possible to display or hide some values in certain condition in Inspector?
For instance, if developer check something in Inspector, then display additional stuffs there.
One way seems to work via overriding the Object class get set and _get_properties_list. I found this old qa entry for this (godot 2.x): https://godotengine.org/qa/3196/how-add-subcategories-inspector-script-variables-section
As these methods still exist, https://docs.godotengine.org/en/3.1/development/cpp/object_class.html it might be worth trying this in Godot 3.x (I didn't try this so far.).