Is there anything like CAG but for Plato?
I’m sure it’s reasonable to think that anyone who could answer this question would know what ‘CAG’ means, but I don’t and I’m curious.
If by CAG you mean the ancient commentaries on Aristotle, there are quite a few in the same series on Plato. For example, Proclus, Hermias, and Olympiodorus. Here is one example: https://brill.com/edcollbook/title/901?language=en
Here is another reference on CAG.
http://www.ancientcommentators.org.uk/concordance-with-cag.html