You can disable the “User Activation Email” notification under Admin--> General Settings→ Email Notifications to sign up for Freshservice. However, there is no email notification present for the ''User invitation'' email which gets auto-generated from the backend. Read below to understand the difference between User Activation Email and User Invitation Email.

User Activation Email: This email is sent to the users once they have signed up for a Freshservice account while they have previously signed up for Freshdesk,Freshchat, Freshsales or any other product part of the Freshworks Organization. This can be edited from Email notifications and can be enabled/disabled.

User Invitation Email: This email is sent to the users once they have newly signed up for Freshservice or any other account part of the Freshworks Organization. They will not be a previously existing user of any product of Freshworks, in this case. For disabling this, please reach out to support@freshservice.com