if you set in the Icon KCM at advanced options set effect to default icons for all Icons all icons were colored but if you want to change only the coloring in an group it doesn't work. Reproducible: Always
Created attachment 97804 [details] set color effect to all icons
https://bugs.kde.org/show_bug.cgi?id=360335
The application would have pass this "group" information, but it only has the name of the icon, and does not know from which group it came from.
Yeah, I don't think this is technically possible, sorry. :(
*** Bug 360335 has been marked as a duplicate of this bug. ***