I think I see what you’re doing here. So you’re trying to add a reference to each of the players by the event begin play so when the host starts, it runs to add it to the array in the gamestate then what you want to happen is when the client joins it runs the event begin play and adds it to the array correct?
If that is indeed the case, a client can’t affect a GameState. I think a Player state could be used and then ran as server to execute and disburse the message that way but in order to carry the reference, you need to have the player controller set as an input pin all the way through every custom event node until it got the the array to be referenced.
you also need to be pulling the data for both instances from the gamestate once it’s been set. I have an example of this on a project that I did something very similar w/ a 3d widget that updated player ready and such and replicated it to clients.