Are all my emails created as tickets in Zendesk when I connect my Gmail as a support address? Will the recipients of those emails get a notification?
All existing Gmail emails will not create tickets in Zendesk.
An option to import 50 of the most recent emails is available. Check or uncheck the box next to Create tickets from last 50 emails when adding your Gmail address.
Zendesk won't send notifications to the recipients of the imported emails upon creation. For full details, see the article: Enabling automatic ticket creation for your Gmail inbox.