I ran to view the contents of a shadow file for a user:
sudo plutil -p /var/db/dslocal/nodes/Default/users/<username>.plist
but when I get to Default it says permission denied, either as a user or root, any ideas?
10.14 protects these files with SIP, so even root cannot access the files without using the directory services command. If you need to get this information deactivate SIP. Remember to reactivate SIP after you are finished. If you attempt to access using the directory services call shown above then you do not need to deactivate SIP.