Definitely not trying to just synthesize modernism and postmodernism but rather integrate them and everything before into a new “holon” – so transcend and include rather than synthesize.
This is an important question and i’d like to say more … and for now …
The most important point would be to focus on Integral/Wilber and his sources e.g. Gebser, Habermas etc. A whole good chunk of Sex, Ecology and Spirituality is on this.
Those are the originating thinkers and Wilber is the great synthesizer who generally does a pretty decent job of citing and summarizing others. (Freinacht and the MM stuff is largely derivative Integral). I emphasize that it will be hard to say precisely because it is emerging and it will also be difficult to see if we are still inside the previous paradigms (which most of us still are at least to some extent).
BTW there is an epistemology line in Cultural Paradigms and how they show up against key features e.g. art, epistemology etc – though that’s just a summary and very vague. What you want is the “meat” of that.