### Godot version

4.0-rc6

### System information

Fedora 37, Mesa Intel ADL GT2

### Issue description

Code that works as expected at runtime fails with Nil references to (assigned) exported vars in the editor:

![tool_global_position_error](https://user-images.githubusercontent.com/364501/222031460-ffb1ecbd-5175-4a42-8470-25285ba5f821.png)


### Steps to reproduce

Try to access the `global_position` of a `Node3D` that's assigned to an exported var.

See that it works at runtime.

See that it errors in the editor with:

> Invalid get index 'global_position' (on base: 'Nil').

### Minimal reproduction project

[tool_test.zip](https://github.com/godotengine/godot/files/10856640/tool_test.zip)

GDCLASS(EditorPropertyInteger, EditorProperty);
	EditorSpinSlider *spin = nullptr;
	bool setting = false;
	void _value_changed(int64_t p_val);
protected:
	virtual void _set_read_only(bool p_read_only) override;
	static void _bind_methods();
public:
	virtual void update_property() override;
	void setup(int64_t p_min, int64_t p_max, int64_t p_step, bool p_hide_slider, bool p_allow_greater, bool p_allow_lesser, const String &p_suffix = String());
	EditorPropertyInteger();
};
class EditorPropertyObjectID : public EditorProperty {
	GDCLASS(EditorPropertyObjectID, EditorProperty);
	Button *edit = nullptr;
	String base_type;
	void _edit_pressed();
protected:
	virtual void _set_read_only(bool p_read_only) override;
	static void _bind_methods();
public:
	virtual void update_property() override;
	void setup(const String &p_base_type);
	EditorPropertyObjectID();
};
class EditorPropertySignal : public EditorProperty {