Today i will use the 'SelectionOrder' expression to do this trail effect. Of course, you can do the similar effect with motion blur control or average effect, but sometimes i find the motion blur is a bit cumbersome, and the average effect is not in compositing itself.
Step 1 : Here i make an axis1 connect to a title image, and add a axisC to act as controller.
Step 2 : Do you animation to fly the image title around in axis1.
Step 3 : Duplicate the axis1 branch several times. Here i duplicate it 10 times.Step 4 : In animation menu, select axis2, then in schematic, hold the 'control key', draw a box form left to right, start from axis2 to axis11 to select them.
Step 5 : in animation manual enter expression :
eval(axis1,frame-(SelectionOrder*axisC.position.x))
Step 6 : In axisC, set the postionX to 2, then run the animation. Change the positionX to other value to see what will happen.
Step 7 : Now i will going to set the trail fade effect. Select image2 (which join to axis2), and in the transparency enter expression :image_L1.transparency-(axisC.position.y*2)
Select image3 and enter expression : image_L1.transparency-(axisC.position.y*3)
and do the same for the remains axis.
(Note: because my image is named image_L1, so in my expression, it is image_L1. If you image name is image1, then just use image1.transparency instead)
Step 8 : Set axisC positionY to -14, and run the animation to see the fade effect. Try different fade value (positionY).
Now, you can change the animation anytime by changing axis1, and you can also animate the trail amount and fade in animation.
Step 8 : Set axisC positionY to -14, and run the animation to see the fade effect. Try different fade value (positionY).
Now, you can change the animation anytime by changing axis1, and you can also animate the trail amount and fade in animation. 
