I wanted the same for a list of events I was building. Although it was easier to create groups for each part of the organisation to add their activities, there was a need to present a consolidated view sorted by date.
My workaround was to create another board with just 1 group. Then add an automation to the first board to create an item in the second board on a trigger action- I used a status change as the trigger but you can choose anything that works .
Add mirror columns from the first board to the second board and voila you have a list sorted by date. I also added a column to the second board to capture the group the item was on the first board.
On the gantt view, you need to explicitely select the mirrored timeline column else it looks blank.
Hope this solution works for you