The Motora Z2 Force Edition comes with dual rear cameras. Each of the cameras features a dedicated 12MP Sony IMX386 sensor (same sensor found in the Meizu Pro 6 Plus). The first cameras uses a Bayer RGB sensor, and the second camera uses a Monochrome sensor, both have f/2.0 aperture lens and 1.25-micron sensor pixel size.
The reason the specs of the two cameras are the same is because the Moto Z2 Force is utilizing the information of both sensors to improve the image quality. Once you capture an image, the data from the RGB sensor is overlayed with the monchrome image. Then the Image Signal Processor is using a nearby pixel interpolation algorithm to help better resolve colors and produce an image with better color fidelity, better exposure and less image noise. When the data is fused together, you get a better looking image. The monochrome sensor doesn't have color filters for each pixel, which means that it captures much more light compared to the Bayer sensor. This light intensity data is very crucial for producing a high-quality image and in some ways, it combat the inefficiency of the Bayer sensor in collecting more light photons.
The Moto Z2 Force edition isn't the first phone to come up with dual-cameras that work in tandem with one another. There is a complex algorithm that is used to make sure that you get satisfactory results and best possible image quality when shooting images in a wide variety of situations.
Some phone manufacturers use dual-cameras for other purposes, like offering a secondary camera with a different focal length for better versatility (e.g. telephoto or ultra wide-angle lens). I wish we could have it all, but right now companies focus on either offering better image quality or a second camera with a different field of view.
Having a dual-camera system is definitely one of the main advantages of the Moto Z2. From my findings, there isn't an optical image stabilization on this phone. I think had it had an OIS system, the low-light performance would have been even better. An OIS allows the camera to shoot under the recommended shutter speed for a sharp image and still achieve sharp results.
If you are among those who care about image quality and low-light performance, I think that the Motoroloa Moto Z2 Force Edition phone will give you just that. If you want better versatility, you probably should be looking for a phone with a dual-camera with different focal lengths. I personally love being able to capture usable shots in low-light. I've been so frustrated in the past with phones that were just unable to capture good quality images after 20:00pm because it just too dark. I hate image noise and like many people, I want to be able to shoot photos at night without needing to delete 90% of them later on because lack of exposure and blurred subjects.