Hmmm, if you are making your own map, then this shouldn’t be an issue at all. If you are trying to get it to to this NOT on your own map, however, I think it is impossible for ARK at this time. The reason being, from how I understand what Jslay and Woe were saying (also from my thread RE: widgets), is that it would have to already exist as a trigger box in the map itself. Since the default ark levels do NOT have said trigger boxes for said event, and since the server is pretty much pure code/logic, you wont be able to add a trigger box to the level itself. You CAN add triggers to items etc, but not into the level without creating a TC if I am not mistaken (complete with your own level maps).
IF you are creating your own map, and it still is not working, from what I have been researching to date, it shouldn’t be that hard at all. Essentially, in your level, you will have the trigger boxes set up. From here, you can easily create an event that activates when the player, and only the player, crosses into the trigger zone. This link here actually has a good example of how to do this in a multiplayer environment. If I am not mistaken, the last part of that tutorial is akin to exactly what you are trying to do…that is have a trigger zone that is triggered only for the current client entering it so that only that client can see the information. This process uses replication! https://docs.unrealengine.com/latest/INT/Gameplay/HowTo/Networking/ReplicateFunction/Blueprints/
FYI I am new to UE4 and modding, so don’t think I’m an expert! This is just my understanding of the widgets and replication from researching them the last couple days working on a similar part for my mod.