I didn't watch over 2 hours of jian and dao reviews for nothing okay... on top of another Youtuber's reviews of the jians.
In short: I Just Think scholagladitoria's (and Skallagrim's) reviews of LK Chen's swords to be extremely interesting, given the additional context of the military swords of that era.
Scholagladitoria's review of Tang dao
Scholagladitoria's review of Han jian
But if I must choose the most interesting ones, it's probably the way the Japanese "refurbished" daos that came from China to continue using them/retrofitted it in accordance to the time's aesthetics, and how it affected historians' attempts at dating those swords. Also, this was in another video, but I'm somewhat surprised that the jians were phased out of the military in Han dynasty... I never did get into Chinese history outside of the context of what I'm reading, but 200 AD ish feels really early. A testament to how old the civilization is, I suppose... Also, 8-sided sword profile in early Han jians was a leftover from when they made swords out of bronze.