Xiaomi's Mi 11 Ultra features a secondary display at its rear but has received criticism for the poor implementation of that feature. That is set to change shortly, as new information indicates that an upcoming build will allow modes like video recording, portrait, and a bunch of other camera modes on the rear display.
https://www.notebookcheck.net/Mi-11-Ultra-rear-display-set-to-finally-get-slew-of-camera-features-in-imminent-update.540603.0.html