AFAIK, there are two ways to do this. One way is to create a chat bot with chat modules but I never successfully did that.
There is also
1 | StarterGui:SetCore("ChatMakeSystemMessage", dictionary<Variant> configTable) |
But this function is intended for local scripts. You would have to use remote events to let the server message all players.
An example:
Server Script
01 | local remote = Instance.new('RemoteEvent') |
02 | remote.Name = 'ServerMessageRemote' |
03 | remote.Parent = game.ReplicatedStorage |
05 | function SendMessage(text) |
06 | remote:FireAllClients(text) |
09 | game.Players.PlayerAdded:Connect(function(player) |
10 | SendMessage(player.Name .. ' has joined the server') |
Local Script (in starter player scripts)
1 | local remote = game.ReplicatedStorage:WaitForChild('ServerMessageRemote') |
3 | remote.OnClientEvent:Connect(function(message) |
4 | game.StarterGui:SetCore('ChatMakeSystemMessage', {Text = message}) |
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