You can edit the available Standard Recruiter Templates sent out to recruiters on behalf of candidates at any time. As these are used in core workflows, they can't be removed.
Editing Recruiter Templates
To edit a recruiter template:
Expand Settings.
Go to Templates.
Select Email Templates.
Open any template in the Standard Recruiter Templates section.
Make the required changes.
Click Save.
If you want to create additional email templates to send specifically to recruiters, you'll need to do so using custom email templates.