With the 8 Directions Animation out of the picture, currently there is no predefined way to implement this.
You need to use common sense.
One way to do it for example is to add each direction as an individual animation:
Animation 0 Up
Animation 1 UpRight
Animation 2 Right
Then you can for example check the angle or the key press of the player to change animation.
If W key is pressed and D key is NOT pressed Do = 0 to Animation
If D key is pressed and W key is NOT pressed Do = 2 to Animation
if W key is pressed and D key is pressed Do = 1 to Animation
And you can do something similar by comparing the Angle of the sprite but in order for this to work you need to make sure you check the box in in the path finding behavior to rotate object as it moves on the path.
So then you can say for example:
If Angle > 350 and < 10 Do = 2 to Animation
If Angle > 300 and < 350 Do = 1 to Animation
Obviously you need to experiment with the values.