Apple has given the specification for the iPhone 7 Plus and 8 Plus features. In reviewing the camera features on both devices it appears there is no difference at all. They both have the front facing camera that is a 7-megapixel sensor. Apple didn't change any of the camera features on the new iPhone 8 Plus and has basically installed the same camera from the iPhone 7 Plus into the new iPhone 8 Plus.
Many of the features in the iPhone 7 Plus have been used in the new iPhone 8 Plus. This includes the retina HD display, the screen resolution, camera, the contrast ratio, and the 3D touch features.