I’ve written a few times about relating two different fourfolds and juxtaposing or comparing them in one eightfold diagram. A normal analogy is usually written as A:B::C:D, which means A is to B as C is to D. So if you have two such fourfolds, one way to write it as an eightfold is A:B::C:D:::E:F::G:H. I think a good name for this is a hyper-analogy. I couldn’t really find anything of merit about this concept, but perhaps it goes by another name.
I’m not sure what diagram arrangement shows this the best. Some ideas are 1) A-D are arranged vertically (as well as E-H) and both are arranged horizontally (side-by-side), or 2) A-D are the triangles pointing down, and E-H are the triangles pointing up. Or, 3) A-B can be the upper left and C-D the lower right squares, and E-H can be the upper right and lower left squares. Or, one can use the radial eightfold schema, and have 4) A-D are the triangles on the inside, E-H are the triangles on the outside (or vice-versa).
For example, here I show the Four Causes combined with my Structure-Function. Also, please examine my Eightfold Metaphysics, which combines Space-Time-Matter-Energy with Structure-Function. Additionally, another I like is the one for Tanabata, which relates the astronomical with the symbolized. I could go on and on, and probably will.