When invading Ekko, try to wait inside a bush for him to use his W (and wait for it to expire) before going on to him. When his shield is down, he is much weaker and easier to kill.
Try and place vision inside the river and around his jungle entrances. This will make it harder for him to gank successfully if you always know his approximate location. Having vision in lane bushes will also help prevent ganks as you can spot him setting up his W.
Ekko doesn’t have the healthiest of clears even with his W. If you are a strong dueler, look to invade his jungle and shut him down in the early game.
Locking down Ekko in team fights will prevent him from using his Ultimate R to escape with. Keep track of his Ultimate R in fights as he can use it to either set up an escape or an engage.
Keep vision in typical flanking spots as Ekko will try to set up an engage with his W from out of vision. If you see him running towards you, back up for a few seconds as he would have used his W.
When no team fights are occurring, Ekko will be looking to split push. Avoid leaving him alone in a side lane by making sure there is always someone matching him.
Once Ekko hits level 6, his ganking will be more effective as he can go for deadlier and longer ganks thanks to his Ultimate R. If you see that your allies are low and he’s on that side of the map, communicate with your team and tell them to recall so they don’t die.
Ekko can start ganking once he has access to all 3 of his abilities. He cannot really gank too much unless he has all of his abilities available to him.
When Ekko gets his jungling item completed, his trading power intensifies and he can 1v1 most Junglers if he is healthy.