Beacon of Progress

Every innovation in every era (regional and culture-specific ones excluded), which means playing deep into the late game - so start late: the wiki recommends an Iranian culture in 1178. The engine is hybridisation: set the "Divergent and Hybrid Culture Cooldowns" game rule to Faster, then repeatedly create hybrid cultures - a hybrid inherits ALL innovations known by either parent, so merging with cultures that know different things leapfrogs whole eras. Between hybrids, stay culture head, pump county development (development gates era progression), and point your cultural fascination at whatever's missing. Converging Paths pops on the first hybrid, naturally.