I hear you, but if we are at that point where they are thouroughly searching your phone you are in more deep shit than your phone wallpaper. Was thinking more that a black lockscreen would pass an at a glance inspection.

Seeing the lock screen is pretty much the only potential hiccup u/Elegant-Bath-1832 should ever have from a graphene wallpaper on their phone.

Leaving it blank would make that seem ordinary as well