The Japanese in 794 built their ancient capital, Heian-Kyo or Kyoto, modelled after the Tang Dynasty capital, Chang'an. As a result, the modern Kyoto reflects some characteristics of Tang Chang'an. Similarly, the Korean Silla dynasty modeled the layout of their capital of Gyeongju after the Tang capital
About Suzhou and Lijiang architectures, since they are in the south side of Yangze river, rains a lot, so their architectures are a bit different from the north wich means the roofs are more steep and more beautiful... From Tang dynasty, I don't think they changed a lot. so among these buildings, you can find 200 years old, 500 years old, even 1000 years old, and it's not that easy to tell...