Thank you for your quick response!

1. The arguments DO NOT work on the vs_installer.exe. This feels weird as the installer is already in place. Would be nice If you could make this work on vs_installer.exe too.

2. If I download the vs_community.exe, vs_enterprise.exe, or vs_professional.exe and run them with the provided arguments it works.

Here is the PowerShell to automate the process:

Write-Host "Update Visual Studio Installer" -ForegroundColor Cyan
$vsCommunityDownloadUrl = "https://download.visualstudio.microsoft.com/download/pr/" + 
                          "8a973d5d-2ccb-428c-8204-290a15d30e2c/be8c694b12879a8f47f34369d55d453c/" +
                          "vs_community.exe";
$vsSetupDirectory = "C:\Program Files (x86)\Microsoft Visual Studio\Shared\Setup";
$vsCommunitySetupPath = "$vsSetupDirectory\vs_community.exe";
if((Test-Path -Path $vsSetupDirectory) -eq $false){  
  $r = md $vsSetupDirectory
}
if((Test-Path -Path $vsCommunitySetupPath) -eq $false){  
  Write-Host "Downloading VS Setup from $vsCommunityDownloadUrl..." -ForegroundColor Gray  
  (New-Object System.Net.WebClient).DownloadFile($vsCommunityDownloadUrl, $vsCommunitySetupPath);
}
Write-Host "Starting the VS setup to update the VS Installer" -ForegroundColor Gray
$installerUpdateProcess = Start-Process `
  -FilePath $vsCommunitySetupPath `
  -Wait `
  -PassThru `
  -ArgumentList @(
    "--update",
    "--quiet",
    "--wait"
);
$installerUpdateProcess.WaitForExit();
Write-Host "vs_community.exe exited with code: $($installerUpdateProcess.ExitCode)" -ForegroundColor Gray

Write-Host "Update Visual Studio" -ForegroundColor Cyan
$vsUpdateProcess = Start-Process `
  -FilePath "C:\Program Files (x86)\Microsoft Visual Studio\Installer\vs_installer.exe" `
  -Wait `
  -PassThru `
  -ArgumentList @(
    "update",
    "--installPath `"C:\Program Files (x86)\Microsoft Visual Studio\2017\Community`"",
    "--norestart",
    "--quiet",
    "--force"
);
$vsUpdateProcess.WaitForExit();
Write-Host "vs_installer.exe exited with code: $($vsUpdateProcess.ExitCode)" -ForegroundColor Gray

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