SftpService | Working with SFTP in .NET Core | Command Line Interface library

This is not intended as an answer (hence community wiki). However, I felt this was important, nonetheless, and wouldn't be possible to cover clearly via a comment.

You should not inject IConfiguration into a service like this. That creates a tight coupling between your configuration and the service, both the method of obtaining the configuration (Microsoft.Extensions.Configuration) and magic strings like MySection. If the format of the config should change, your service will break, because it's depending on things (both the knowledge that there's a MySection section in the config, and how that config is retrieved) that it shouldn't actually know anything about.

Instead, you should always just inject the information you actually require, i.e. the values of Host, Username, Password, etc. When there's a lot of tokens like this, you might instead consider creating an options class to encapsulate them, and then inject that instead. For example: