QUESTION
Can Copilink copy trades across different computers or different NinjaTrader installations?
No. Copilink copies trades within a single NinjaTrader 8 instance on one computer.
All accounts (leader and all followers) must be connected to the same NinjaTrader session on the same machine.
For multi-computer setups: Use a VPS and connect all broker accounts to that single NinjaTrader installation.
Copilink is not a signal service and does not communicate over the internet between machines.