What is new in Android 12
(Android 12 is the Lineage OS 19 will be based on)
- new color system and new design
- smoother UI
- accessibility, bold text, magnification etc
- better privacy control, especially on camera and mic
- better UI for permission control
- extending screenshot
- and more on andriod 12 releasing or the youtube video attached
What will Lineage OS 19 will be
Unfortunately, there is no official Lineage OS 19 release yet, the new Lineage OS release usually will be later than AOSP release, but it does not mean users cannot have a look of what Lineage OS 19 will be. The video below is a user who customized Lineage OS 19 based on Android 12 on Redmi Note 7 Prop.
More about Xiaomi and Data leaking if you have a concern about privacy.