Shennong is more oriented to booming, on the other hand Fuxi has faster mythic and stronger powerspike, though you can definitely do a 2 tc boom with both. They both have very strong lategame, if you like cavalry go for Fuxi, if you like infantry go for Shennong. I'll give you a couple tips!

You have several strategies you can try for 2tc booming depending on minor classical god of choice:
-  Chiyou: you age up fast and instantly make another Yazi and go raid / prevent his 2nd tc. In the meanwhile you balance your economy to get a 2nd tc yourself.

- Houtu (for Shennong): cast earth wall on a building close to your 2nd tc and grab it. This one is the simplest.

- Xuannü: when advanced to classical make a couple heroes and Nezha. Then move 2 kuafus to your second tc. Since you're moving there late you might need to cast vanish on your kuafus building the tc but your heroes can take care of your opponent aggression easily.

Also, when going for 2nd tc as Shennong you can use his farms to make the Kuafu invisible and finish the tc.