https://mobilesyrup.com/2019/01/10/google-assistant-will-work-with-android-lockscreens-ces-2019/

Google Pixel lockscreen Assistant feature coming to all Android devices All Android users will soon be able to trigger Google Assistant even if a device is locked By Sameer ChhabraJAN 10, 201910:40 AM EST0 COMMENTS

Google Pixel users can already allow Google Assistant to activate when a device is locked, but the feature will soon be available for all Android users. According to a January 8th, 2019 Google media release, Google Assistant will soon be able to respond to queries “even when your Android phone is locked.” “You can ask your Google Assistant to show restaurants nearby, set up and dismiss alarms, schedule reminders and timers without unlocking your phone,” reads an excerpt from the same January 8th media release.
Read more at MobileSyrup.comGoogle Pixel lockscreen Assistant feature coming to all Android devices