You dont need to activate it to test it. You will be limited in distance and altitude but you can check out all functions, gimbal tilt/rotation, video, photos, gps etc. You will not be able to test distance or signal strength.
Sport mode will not disable the bottom sensor, only horizontal. To disable all sensing go to Settings-Safety-Advanced Safety Setting, at the bottom turn off Vision Positioning and Obstacle Sensing. Read warning explaining what it does and press...
I'm not sure how "set iso to auto and don't be in DLog" isn't clear, but if it doesn't make sense then just go full manual and the camera will work as it always did.