Hello,
I think you should try to understand each pieces of the puzzle separately before trying to plug everything together.
For all C# projects, you should use the “SonarQube Scanner for MSBuild” and forget the raw SonarScanner. There is no sonar-project.properties to manually provide, the “SonarQube Scanner for MSBuild” is handling it. So you should follow this documentation: https://docs.sonarqube.org/display/SCAN/Analyzing+with+SonarQube+Scanner+for+MSBuild
Once you will be able to scan your local copy of your project with the “SonarQube Scanner for MSBuild” and send the results to your SonarQube 7.7, then it will be the time to think about automating things with Jenkins.
Regards