Sir, the exchanges have been always two-way , other cultures or ethnicity assimilating Han and Han exporting theirs, throughout the history, Han itself is a fusion of all kinds, so there're Hokkienese Cantonese, Hakka and so on, distinctively different sometimes. Chinese simply don't bother to make life more complicated so we make do with a Han umbrella.
Cultural Revolution was a fiasco but every cloud has a silver lining. Off topic though.
Why Japanese women? No idea as that saying is older than me.
Back to Chinese copying western architectural styles, on local campus
A combination of both Chinese and western styles in 1910's. Chinese are great learners aren't we?