The fonts are not automatically loaded with FFCore. The fonts can be downloaded at http://fonts3.com/fonts/x/XeroxSans-Light.html and http://fonts3.com/fonts/x/XeroxSans-Bold.html . There are other sites that also enable downloading these fonts -- see Google.
Do Xerox Sans and Xerox Sans Light fonts automatically get installed in Windows 10?
I am unable to locate where the fonts are installed.