It is worth noting that in order to do this, the drone would have to be in JOYSTICK mode so Litchi can brake the drone before it hits the virtual wall.
in JOYSTICK mode, the drone will not behave the same as when controlling it manually, something unwanted in a situation where a beginner controls the drone
P-GPS is the standard/default flight mode, in this mode you can control the drone manually with the remote as in DJI Fly. The remote sends commands straight to the drone.
Joystick mode is when the drone can be controlled by a third party app like Litchi. In this mode, Litchi sends required velocities to the drone. Joystick mode is used for most Litchi modes (for DJI Fly drones) other than when you fly manually. We can give you a simulated manual control with Joystick mode, where Litchi calculates and sends required velocities based on the remote controller joystick positions, but that is not true manual control, the drone won’t behave the same as if it is in P-GPS mode. In addition it adds some latency as the commands go from RC → DJI SDK → Litchi → DJI SDK → RC → Drone rather than just RC → Drone
The custom geo-fencing function will be important for today’s aerial photography and videography. In my flight permit application, to avoid flying over main highways or buildings, our civil aviation department requested us to use software that can provide a custom polygon geo-fence function instead of using the DJI Fly app or Go 4 or Litchi basic Max distance flight function. Most of the time, when we set up a radius big enough to cover our target subject, the drone will have a chance to fly over the main highway if it flies away. Litchi, to me, is my favorite program for Inspire 2. Without it, achieving the desired result using DJI GS Pro will be tough. Maven is only available for Mavic Air 2S and is incompatible with Inspire 2. Honestly, Litchi will be much more popular with a custom geo-fence function, especially under the tight monitoring of the civil aviation department in HK.