While there is a long history of reverse engineering isnt it equally likely that if you give two teams of engineers the same brief and the same computer simulation models they will come up with virtually the same design because in our data defined world that's what we should expect to happen.
Take a look at car design , small com[acts (not the actual mini) mostly look the same small-mid SUVs look the same etc etc . A few examples from history , British Vc 10 , long haul good field performance need to operate from lower grade airfields than main hub .Russian ILK62 long haul 4 engines good field performance and operating from second-grade airports , the result they look largely the same.
Four engine pure jet transport capable of transcontinental transatlantic operation version 1 B707 version2 DC 8 , how many pax could tell them apart.
So don't be too sure about the Chinese copying things, based on their huge population and all they have learned in the last 40 odd years they are no longer second class scientist and engineers often ignorant of technological development due to Chinas place in the world (ie seperate from it) . We will/are underestimating them at our peril, they have huge resources, no greedy ignorant shareholders wanting unrealitic paybacks and can take a long term view. And vast number sof their besta nd brightest engineers went to all the same western univeristies as their peers in the west.