FYI Brian, the 12-42 is actually lighter than the DJI stock lens.
Yes, I know that, but weight isn't the only factor. In fact, the real thing here is a thing called "moment" and is the torque applied which is due to a combination of weight and the location and distribution of that weight. You can have two lenses that weigh the same and one will balance perfectly while the other will need to add weight somewhere to balance.
The problem with the 14-42 like many zoom lenses is that as the zoom position changes the lenses elements move changing the moment on the gimbal. I'd recommend that if you plan to use the lens through the whole zoom range that the lens be balanced when the lens is in the midway position. That midway position may or may not equate to the mid position of the zoom range.
Bria