[GAMEPLAY] An oathsworn Ekko can't trigger Kalista's W passive with his E

When playing a Kalista/Ekko duo lane, Ekko can't trigger the bonus damage from the Soul-Marked passive on Kalista's W with the long range basic attack given to him after using his own Phase Dive. The first basic attack will teleport him to the target, but he must attack again before the bonus damage applies. Because the tooltip on Ekko's E states that "his next basic attack" teleports him, and because this attack applies other on-hit effects such as the bonus damage from Sheen items, I am assuming this is a bug.

Steps to reproduce:

1. Have Kalista use the Black Spear to bind with Ekko.
2. Have Kalista put a point into her W and Ekko put a point into her E.
3. Have Kalista attack a target to apply the first half of the mark from her W.
4. Have Ekko use his Phase Dive and use the long range basic attack to hit the same target Kalista marked. Expected result: Ekko's basic attack would trigger the bonus damage from Kalista's W in addition to teleporting him to the target, the same way the basic attack triggers other on-hit effects. Observed result: Ekko's basic attack teleports him to the target, but does not trigger the mark. He must attack again to trigger the bonus damage. Reproduciblity: 100%. Has happened multiple times in every game, regardless of items, targeting a champion vs. a monster, or any other factor. Proof