Default Plasma Plasmoids currently do not follow Accent Colors scheme.
Here are some Proposals for tighter integration:
1. Accent color palette Generation
Accent color palette generation a la Android would help users automatically theme plasmoids and other colors across KDE more efficiently imo. Maybe the palette can generate upto 6 colors which can be invoked using relevant plasma libraries (sorry I am not well versed in plasma libraries/backend).
Samsung’s implementation:
2. Accent Color (or palette) as a toggle in plasmoid colors
Changing the color on each plasmoid individually after a wallpaper change feels too tedious of a task. The plasmoid can request KDE to provide the accent color or the user can override the accent color for custom colors. e.g.
In my screenshot I manually use a white and a lime as an accent to the wallpaper.
In Binary Clock:
The “Use Custom Color” can very easily also turn into a list like this messy mockup I made:
I would love to see a unified color theming in KDE.