A script that changes the colors of the folder icons from breeze dark. It uses the colors take from other folder icons in the theme.
I should also mention that these are available in the store here. Also you can find a similar (but missing the gradient) icon set here which sinks with your color scheme, but I find them not too look as good.
git clone https://gitlab.com/RaitaroH/BreezeDarkIconColors.git
chmod +x BreezeDarkIconColors/ChangeColors.sh
Simply run ChangeColors.sh --command. You can use the -h|--help to see what you can do. You can change the folder icons to purple, green, red etc.
After the script did it's thing, you have to change the icon set from System Settings.
Also you can try out my color scheme changer here to have a more fitting qt theme.
A few examples:
