Yeah that’s the self-centering mechanism (activated by the optical hand sensor) of the joystick, it’s not actual force ‘feedback’.
Until the FSforce update is released or some other implementation of dynamic forces, you can adjust these static parameters with simFFB
Here’s an updated version with a few extra features added (not my work, original simFFB program by average_pilot) : https://github.com/joeyjojojunior/simFFB/releases/tag/v3.2
(note, closing the application usually disables all centering forces. Normal/default behavior returns after a reboot)