The post at 13 Jan 2020, 23:29 suggests it is possibe to show different blink patterns (but ofcourse all white). It would be interesting to find out how to trigger these different modes.
As for disabling the charging- or message received indication what would be the best way? A menu in the system settings? A config file in phablets home dir?
The led notifications are guarded by a unity8. How can unity8 detect what phone/hardware it is running on?
-Edit-
I have been working on a way to disable showing charging state.
See https://github.com/ubports/unity8/pull/283