Hao Ran, a OnePlus employee, has shared one of its designs for its early 2018 flagship. It exchanges the glass rear panel normally found on this phone (the 6) for a more original backing made of wood. This render's non-optical fingerprint sensor and logo were also picked out in gold, which went well with the phone's alternative finish.
https://www.notebookcheck.net/A-OnePlus-designer-shows-off-what-the-6-could-have-looked-like.450878.0.html