Apple looks to be working on an in-display Touch ID solution for a future iPhone, possibly in time for a 2020 or 2021 release. With most of the flagship competition working hard to eliminate notches for a truly all-display design, it looks as though Face ID may be on the way out.
https://www.notebookcheck.net/2020-or-2021-iPhone-could-bring-back-Touch-ID-but-in-display-this-time.421921.0.html