Passing mouse through remote events?

The Mouse Object is becoming obsolete i would recode it using the UserInputService

But for now this is a way on how to solve the problem you're facing at the moment....

Code:

Server Script

local replicatedstorage = game:GetService("ReplicatedStorage")
local re = replicatedstorage:waitForChild("RemoteEvent",10)
local Mouse = {
	Wheel = 0,
	Button1Clicked = false,
	Button2Clicked = false,
	Position = Vector2.new(),
	Target = nil,
	Hit = nil
}
local MouseFired = false
local function event(player,mouse)
	
	for k,v in pairs(mouse) do
		Mouse[k] = v
	end
	MouseFired = true
end

re.OnServerEvent:connect(event)


while true do
	if(MouseFired == true) then
		MouseFired = false
		print("Mouse: ")
		table.foreach(Mouse,function(a,b) 
			print("a ",a," = ",b) 
		end)
	end
	
	wait()
end

Local script

local replicatedstorage = game:GetService("ReplicatedStorage")
local re = replicatedstorage:waitForChild("RemoteEvent",10)

local player  = game.Players.LocalPlayer
local mouse = player:getMouse()
local MouseWheelZeroTime = 0.01
local Mouse = {
	Wheel = 0,
	Button1Clicked = false,
	Button2Clicked = false,
	Position = Vector2.new(),
	Target = nil,
	Hit = nil
}

mouse.WheelBackward:connect(function()
	Mouse.Wheel = -1
	re:fireServer(Mouse)
	wait(MouseWheelZeroTime)
	Mouse.Wheel = 0
	re:fireServer(Mouse)
end)

mouse.WheelForward:connect(function()
	Mouse.Wheel = 1
	re:fireServer(Mouse)
	wait(MouseWheelZeroTime)
	Mouse.Wheel = 0
	re:fireServer(Mouse)
end)

mouse.Button1Up:connect(function() 
	Mouse.Button1Clicked = false
	Mouse.Target = mouse.Target
	Mouse.Hit = mouse.Hit.Position
	re:fireServer(Mouse)
end)

mouse.Button1Down:connect(function() 
	Mouse.Button1Clicked = true
	re:fireServer(Mouse)
end)

mouse.Button2Up:connect(function() 
	Mouse.Button2Clicked = false
	re:fireServer(Mouse)
end)

mouse.Button2Down:connect(function() 
	Mouse.Button2Clicked = true
	re:fireServer(Mouse)
end)

mouse.Move:connect(function(thing)
	Mouse.Position = Vector2.new(mouse.X,mouse.Y)
	re:fireServer(Mouse)
end)

So in your Server script just remember you're working from the Mouse Table and not the Mouse object! As you cannot pass the mouse object from a local script as you know. So the above example is Side-stepping that problem and re-creating the Mouse object on both Client and server scripts through the use of a table in both. The only other problem i can foresee is if many people are playing the game you may get Exceeded number of callback Errors and scripts breaking due to the amount of data being sent.

To reduce the amount of data being sent through the Client Server Boundary I would limit the amount of calls to the server from the client. For instance if you're placing a block and wanted it to show on the screen at the mouse cursor point i would replicate or fake it in the client script and only when you place it down via Mousebutton1Click, send the updated data to the server. And if you wanted others to see it I would only update that once per second or something.

That way it drastically reduces the amount of calls from the client.

Just some ideas

Hope this helps! :)

For reference on the UserInputService you can check out the wiki here: https://developer.roblox.com/en-us/api-reference/class/UserInputService