I just tested this out, and I think I can answer what the difference is. With the Heart Hex, you teleport directly to your target, while with the Spade Hex, you can jump while in the process of going to your target, giving you more momentum with your jump. Honestly, I think that the video example provided with the Spade Hex just doesn't show the ability properly, in the sense that it shows Beebz jumping away from the Target after already reaching it