LinqPad Script that generates the GraphViz file to visualize dependencies.

ProjectDependencies.cs

void Main()
{
	//Generates the .gv file content that can be put into GraphViz to vizualize your dependency tree.
	//	Once in GrpahViz, export to svg to avoid guessing how big you will need it (e.g. compared to PNG/JPG or other raster formats)
	var rootPath = @"C:\source\GitHub\Mercury";
	var outputPath = @"C:\source\GitHub\Mercury\references.dot";
	
	var limit = 1000;
	var projects = Directory.GetFiles(rootPath, "*.csproj", SearchOption.AllDirectories)
		.Where(path=>!path.ToLowerInvariant().Contains("test"))	//Exclude tests for sanity
		.Select(path => CreateProject(path))
		.ToArray();
		
	var sb = new StringBuilder();
	sb.AppendLine("digraph G {");
	sb.AppendLine("size = \"50,50\"; ");	//Size in inches.
	
	foreach (var project in projects.Where(p=>p.Index < limit))
	{
		sb.AppendLine($"{project.Index} [label=\"{project.Name}\", shape=component, style=filled, fillcolor=LightBlue];");
	}
	sb.AppendLine();
	foreach (var project in projects.Where(p=>p.Index < limit))
	{
		foreach (var refId in project.ReferenceIds().Where(idx=>idx < limit))
		{
			sb.AppendLine($"{project.Index} -> {refId} [ ];");
		}
	}
	
	sb.AppendLine("}");
	sb.ToString().Dump();
}

// Define other methods and classes here
private static Project CreateProject(string fullPath)
{
	XmlReader reader = XmlReader.Create(fullPath);
	XElement root = XElement.Load(reader);
	XmlNameTable nameTable = reader.NameTable;
	XmlNamespaceManager namespaceManager = new XmlNamespaceManager(nameTable);
	namespaceManager.AddNamespace("defaultNamespace", "http://schemas.microsoft.com/developer/msbuild/2003");
	var elements = root.XPathSelectElements("//defaultNamespace:ProjectReference", namespaceManager);
	
	var relativeReferences = elements.Select(e => e.Attribute("Include").Value);
	var currentDir = Path.GetDirectoryName(fullPath);
	var absoluteReferences = relativeReferences.Select(r => Path.Combine(currentDir, r))
		.Select(p => Path.GetFullPath(p).ToLowerInvariant())
		.ToArray();
	return new Project(Path.GetFileNameWithoutExtension(fullPath), fullPath.ToLowerInvariant(), absoluteReferences);
}
public class Project
{
	private static int NextIndex = 0;
	private static Dictionary<string, int> _fullPathToIndexMap = new Dictionary<string, int>();
	public Project(string name, string fullPath, string[] fullPathReferences)
	{
		Index = NextIndex++;
		Name = name;
		References = fullPathReferences;
		_fullPathToIndexMap[fullPath] = Index;
	}
	
	public int Index { get; private set; }
	public string Name { get; private set; }
	public string[] References { get; private set; }
	public IEnumerable<int> ReferenceIds()
	{
		foreach (var fullPath in References)
		{
			int value;
			if (_fullPathToIndexMap.TryGetValue(fullPath, out value))
			{
				yield return value;
			}	
		}
	}
}