public interface IModdedChivalry2Launcher
{
    public Either<ProcessLaunchFailure, Process> Launch(ModdedLaunchOptions launchOptions, IEnumerable<string> args);
}

public class ModdedChivalry2Launcher: IModdedChivalry2Launcher { 
  private IProcessLauncher Launcher { get; }
  private string WorkingDirectory { get; }
  private IModManager ModManager { get; }
   
  public ModdedChivalry2Launcher(IProcessLauncher, launcher, string workdir, IModManager modManager) { 
    Launcher = launcher;
    WorkingDirectory = workdir;
    ModManager = modManager;
  }

  public Either<ProcessLaunchFailure, Process> Launch(ModdedLaunchOptions launchOptions, IEnumerable<string> args) {
    // ... impl ...
  }
}

public class SomeViewModel {
  // ...
  private IModdedChivalry2Launcher Launcher { get; }

  public SomeViewModel(IModdedChivalry2Launcher launcher) {
    Launcher = launcher;
  }

  public void SomeLauncherInvokingFunction() {
     // ...
     Launcher.Launch(foo, bar);
     // ...
  }
}