So the point is, can i spawn joined player to a randomized position and old joined player spawned on the last place he moved (not by randomized) ? maybe you can help with the events that should i put..
You spawn player object once, most likely on joined client. Then you create object copies on other clients.
For original object, you set position explicitly (e.g. using random numbers). For object copies, you synchronize position with original object each time this position changes including initial position assignment. Also, each existing client should send position update to a new joined client.