The feature is broken. Something happened when new engine releases came in and nobody noticed that the wakes were not visible anymore. When you posses a bot with ‘E’ key and you move it, you can see the BP_Wake actors being spawned and destroyed, but they are not visible. There is a camera position I discovered that you can see the wakes visible, but any change they go poof again.
The method is consistent, but it would be necessary to look the last engine version this worked as it should and start to compare engine source code changes that made this behavior to happen, takes a huge amount of time, which I don’t have right now.
PS: I have figured out the issue and will post the changes needed with a small video. It is just a translucency sorting issue.