Is there a way to deploy a Pega Robotics package directly to Package Manager instead of through Visual Studio. Our client has a policy for production environment in which all packages need to be scanned before Admin deploy it as files in a specific folder.
Probably, no. Package Server works with Robot Manager. When you deploy with Visual Studio, Package Server gets deployment package while Robot Manager gets package metadata and they should be in sync with each other.
Please note that while metadata and code is uploaded to Package Server and Robot Manager it is not applied to Runtime machines unless you deploy it in Robot Manager. Maybe you can scan package at this stage - files are available on machine where Package Server is installed.
Another way is to unset "Publish to Server" during deployment in Studio. In this case it generates package locally but doesn't upload it. You can run "Deploy" again and publish after scan.