Liyue Harbor is supposed to be the most prosperous commercial port in all of Teyvat (literal in-game quote) but it has never received any samples of foreign technology or inventions to be sold to the elite or to be brought back by native Liyue merchants who brought inventions back home
Also all of sudden Nod-Krai is actually where travellers, adventurers and merchants all converge instead but we kind of forgot to mention this until the region was namedropped for the first time in version 5.X