Definition of flight mode (horizontal movement)

For a number of applications (spraying in agriculture) or taking loads that only can be carried level, one can imagine a multicopter that can move forwards or sidewards without tilting or rolling. This can be achieved using fixed slightly tilted rotors that are managed such that they give a driving force, or by vertical separate truster units or by flaps diverting the airflow under the rotors. Such level flight multicopter system is not yet in the arducopter software. So there are 2 questions the team might be helpful with: is there a term for such level movement of a drone; what level of effort would it take to change/add the firmware for such system? Eg starting with 2 horizontal trusters that can do both forward and sideward movement. The joystick would be used for the same forward sideward, but not the angle of the drone but directional speed/acceleration would be the control values?

Hope to hear from the team