The Delete (Node Template) command deletes the selected node template from the project. You will be prompted to confirm the deletion before the icon template is removed.
Since node templates are defined per-project, this means that no other project team members will have access to this template for the selected project. However, deleting a node template from one project will not affect any other project.
Node templates marked as essential are internally referenced by GENESYS and key to its proper operation, even if the particular node template is not one that you choose to use. Essential node templates cannot be deleted. If you attempt to do so, you will notified that the icon template is essential, and it will not be removed from the project.