Yes, you can :-)
1. In the Timelines panel, control/shift click the transitions you care about.
2. Click the arrow to the right of the "Smooth Transitions" button to show the Smooth Transition Options dialog. Adjust options in this dialag as you desire.
3. Click the "Smooth Transitions" button in the Timeline.
All the selected transitions will be smooth according to your options
- By default, smoothing will not change effects you have manually edited or added. To make the timeline clear out customizations you have made and just create new smooth effects, then check the "overwrite existing effects" option in the Smooth Transition Options dialog
- The "Fade Out - Move - Fade In" option in the Smooth Transition Options dialog gives you a common transitions design pattern. All objects disappearing from a state will fade out first, followed by any objects that move/resize/rotate, followed by objects that fade in to the new state. An example of where to use this is in a collapsible panel that hides and shows content. You don't want the panel to resize and collapse before its contents have faded out first. This option gives you that effect.