Feedback

I think it would be good to have a specific example of one of the GNNs models (the most basic one) so that we can see how it works. And then explain how the other models extend this. At the moment is too superficial for your peers to be able to understand GNNs from your description. This of this as a teaching moment; you want to teach your peers about GNNs so they get the basic idea(s).

Also, what does a GNN represent / learn? Properties of nodes? Properties of arcs? Missing arcs? Properties of the whole graph? Do they assume the graph structure is known? For learning a graph, be explicit about what is input and what is output.

(Also please fix the math; sometimes you use $ when you should use <math> (I think)).