The KNOX Workspace may contain different 3rd party apps based on the region the device originates. If you would like to hide/disable these apps please use the following API from the Application Policy class.
public boolean setDisableApplication (String packageName)
If you are using a EMM to manage your devices please check with them to see if they have implemented the above API.
Note - Google services by default are disabled inside the KNOX container. If you see Google apps inside the container, please check the EMM console if any related policies are enabled.
If you need further assistance please log into www.samsungknox.com and create a ticket.