Wake my my phone using "OK Google."

just reading through this thread, and wondering if my phone it's different to everyone else, because my phone (Samsung S9) DOES unlock from the 'sleep' screen by saying "ok Google". (there's a setting within Google Assistant) i use the function all the time while driving, it's very useful for a completely hands free experience.

HOWEVER, I'm not convinced by the security of voice unlock (much prefer face/iris/fingerprint) so what I would prefer is to be able to use Google Assistant WITHOUT unlocking the phone. This doesn't seem to be an option at the moment, unless I've missed something somewhere
 
@djn83 is there an "Always-on" setting next to your "access with voice match" toggle?

For your question about lock screen security. maybe with the "unlock with voice match" toggle (under access toggle) there is a setting for "personal results?"

When your screen is locked
Unlock with Voice Match:
When you say "Ok Google" from a secure lock screen and we're able to recognize the sound of your voice, you can ask Google to take actions for you or visit sites without having to unlock your device manually.
Personal results:
See personal results for your voice searches, even when your device is locked.


That is from search result for "Use 'Ok Google' voice searches & actions."