Unfortunately the encrypted phone market is a total mess. The Darknet Diaries podcast has a good episode about this. https://darknetdiaries.com/episode/105/
Nothing has to be on your phone for a cop to demand its contents. At which point, if they want to find something incriminating, rest assured they will.
“Nothing to fear if you’re not doing anything wrong” is a fallacy that serves only the cops
A compact Linux device without any biometrics, telemetry, public clouds and corporate spying software is probably what you could be looking for.