For more information, please refer to this announcement explaining best practices for getting answers to questions.
Combine Task Notifications for Personally Created Journeys
When creating a Journey through "Checklist Templates," there is an option to "Combine Task Notifications" under the Display Settings section. This option allows all task notifications (which would go out individually to the assignee) to be combined into ONE notification, with a list of all tasks within the journey contained in that notification. This has been immensely helpful functionality to prevent email "vomit" or spam being sent to our users, and is currently in use for our triggered journeys like onboarding today.
HOWEVER, when it comes to individual journeys that are created and assigned through the VB front end of Journeys (I.E. Me, My Team, MCG -> Journeys -> Explore), we as an org cannot find a single option that even addresses the ability to limit notifications, combine notifications etc. So if we have an HR Rep go and create a personal journey, and then assign it to say, 5 individuals, those individuals will receive 15 notifications for each of the 15 tasks in the journey.