Graphene OS is great but it can only be flashed to Google Pixel phones.
It’s possible to buy a Pixel and turn it on without needing to enter a Google account upon startup and the process to flash Graphene is extremely easy to do.
Discussion
The easy webusb flashing requires Google Chrome last I read. Not Chromium, Brave or Firefox. Not Chrome flatpak or snap. Chrome from Google giving it same privileges as native system apps.