Do you think the Saudis would want to buy a deliberately gimped plane (even if the original is the most advanced flanker)? And if they did, do you think China would be willing to spend the r&d, manpower and resources to create a separate supply chain for this export variant? That's a lot of time and energy that would be better spent building planes for the PLA. It's not like China needs money anyway.China purchased SU-27 produce in mainland as J-11 under license agreement with Russia and made promise, they will never sale this aircraft to any foreign customer. that's it
J-16 and J-15 these two flankers have nothing to do with Russian permission. China derived J-16 from J-11.
but yeah agreed with your second point. but China can sale J-16 with inferior avionics. another point, prize is too damn high for China to ignore. Saudi in China's camp is a huge victory.
I think the more likely scenario is sale of C919 or less sensitive tech like JF-17.