The Sam Levinson-directed Assassination Nation drew the biggest acquisition and became the buzziest title at January’s Sundance Film Festival. Today, the shocking and provocative film shoved aside the superheroes and usual fanboy fare from Hall H as the filmmakers took the stage to try to broaden its potential appeal to include the young-demo San Diego Comic-Con crowd. The Bron-backed pic was acquired by Neon, and Joe & Anthony Russo’s AGBO in a $10 million-plus world…