I'm not 100% happy with the design yet (hence why I was asking in the other thread!) but I mocked this up for a timeline that may or may not go anywhere, with a quintuple monarchy uniting Catholic southern Germany and Austria-Hungary under the Habsburgs. I borrowed the coat of arms from wikimedia and then tried to measure out the sub-flags. The large red stripe represents Austria, the green is Hungary, the light blue is Bavaria, the yellow is Lothringen (Lorraine), and the deep blue is Croatia. I'm very much open to suggests on how to make this better or for better ideas on how to incorporate these states vexillologically!