# Load WinSCP .NET assembly
Add-Type -Path "WinSCPnet.dll"
 
# Set up session options
$sessionOptions = New-Object WinSCP.SessionOptions -Property @{
    Protocol = [WinSCP.Protocol]::Sftp
    HostName = "example.com"
    UserName = "username"
    Password = "password"
    SshHostKeyFingerprint = "..."
}
 
$session = New-Object WinSCP.Session
 
# Connect
$session.Open($sessionOptions)
 
$localPath = "C:\local\source\path"
$remotePath1 = "/remote/reference/path"
$remotePath2 = "/remote/target/path"
 
$remoteFiles = $session.ListDirectory($remotePath1).Files | Where-Object { -Not $_.IsDirectory } | Select-Object -ExpandProperty Name
$localFiles = Get-ChildItem $localPath | Where-Object { -Not $_.PSIsContainer } | Select-Object -ExpandProperty Name
$changes = Compare-Object -DifferenceObject $localFiles -ReferenceObject $remoteFiles
 
$added =
    $changes |
    Where-Object -FilterScript { $_.SideIndicator -eq "=>" } |
    Select-Object -ExpandProperty InputObject
 
foreach ($filename in $added)
{
    Write-Host "Uploading $filename ..."
    $localFilePath = Join-Path $localPath $filename
    $remoteFilePath = [WinSCP.RemotePath]::CombinePaths($remotePath2, $filename)
    $session.PutFiles($localFilePath, $remoteFilePath).Check()
}