Stop-Service cannot stop services remotely. One easy way of doing so is Set-Service:
Set-Service -Name Spooler -Status "Stopped" -ComputerName targetcomputer
However, unlike Stop-Service, Set-Service has no -Force parameter, so you cannot stop services if they, for example, have running dependent services.
If your infrastructure supports PowerShell Remoting, you could use Invoke-Command instead:
Invoke-Command { Stop-Service -Name Spooler -Force } -ComputerName targetcomputer
