Style-aware icons for folders in Nautilus / Gnome Files

I'm running Gnome 3 on Fedora 25, and many of the xdg-compliant standard user directories (like "Desktop", "Downloads", "Public", etc) have a special icon when viewed in Nautilus (i.e. the Files app). These icons also change to match the active GTK Icons theme, as managed by Gnome Tweak Tool.

Is there a way to make Nautilus use such a style-sensitive icon for custom folders? I ask because I want to make a Templates folder (to use the features mentioned in this Fedora Magazine article), and I'd like Nautilus to show that folder with Gnome's default set of "Template Folder" icons, located at:

/usr/share/icons/<theme>/<size>/places/folder-templates.png

I know how to set a file/folder's icon to a specific image (discussed here for reference), but not how to set an icon to one that will follow the active GTK Icon theme.

Is there a way to do this? Or are the style-aware icons hard-coded in Gnome/Nautilus and can't be customized?

EDIT: Looks like Nautilus uses the correct, style-aware Templates icon after all. I set ~/Templates as my XDG_TEMPLATES_DIR via 'xdg-user-dirs-update --set', and now Nautilus is using the right icon for Templates. But my question still stands for folders that aren't xdg user directories.