A couple of Apple Watch-related patents could give an indication of the direction Apple is taking in regard to a potential Apple Watch Series 7 device. One of the patents details a Touch ID button for the smartwatch while the other reveals an under-display camera solution that would make an Apple Watch 7 ideal for quick FaceTime video calls.
https://www.notebookcheck.net/Apple-Watch-Series-7-with-under-display-camera-and-Touch-ID-button-could-become-a-reality-if-related-patents-come-to-fruition.510358.0.html