You can finally set a custom Material You accent color in Android 12, but your choices are limited
(Android Police)

Beta 3 also includes a redesigned wallpaper picker Google is delivering its first significant visual redesign in years with Android 12, and along with it comes a theme engine capable of customizing your smartphone in just a few simple steps. Material You pulls its slate of color choices from your wallpaper to customize icons, menus, and more. With Android 12 Beta 3, you can finally choose a custom set of accent colors, though some might still find the possibilities just a little too limiting. Read More You can finally set a custom Material You accent color in Android 12, but your choices are limited was written by the awesome team at Android Police.