About six months ago I talked to @Ashyr@sh.itjust.works about home brewing games set in Ancient China. Last night I finally debuted my game - The Scroll of Hengdian. If you like CDramas the name may be familiar as Hengdian Studios is where many series are filmed. My game is based on the Castles and Crusades game system so I could leverage the Codex Sinarum. The codex goes deeper into the actual history of China than my game does, but it is still very useful for this setting.
My TTRPG is xianxia-based so I created a new 'cultivator' class for all of my players. The differentiation really comes with the clan and domain choices that give access to magic based on elemental aspects and creature choices.
I borrowed heavily from the Codex Sinarum to develop the Qi abilities for my characters since that was the heaviest lift for me in terms of developing a new class that is a blending of fighter + wizard/cleric/illusionist. My players chose a blend of human and spirit based cultivators which gives me plenty of nuggets to develop additional qigong abilities.
In terms of content, my players are starting as young cultivators who have met at a sect that has invited them to cultivate and achieve their first level. I also took a random suggestion I saw a while back about creating a Star Trek TNG "Q" type dragon character (Die Lan Zi - iykyk) that occasionally comes around to mess with the party.
Well that's what it's all about!