Is it possible to group items from different boards on a Gantt view?
Did you still need help with this? It sounds like the Gantt Widget on a dashboard would be what you’re looking for. While you would not be able to add items from different boards to a Gantt View, this is definitely possible with the Gantt Widget.
How many boards are you looking to pull from? As a heads up, depending on the plan you have, you will be able to connect a certain number of boards to a dashboard.
I hope this helps