Well, nerf the length and buff the speed, because the jian is a gentleman's sword that everyone in the nobility seemed to carry around all day, so it had to be concealable and comfortable
Also, we DO have many chinese weapons. We have chinese swords, like the yanmaodao, liuyedao, niuweidao, dadao, and miaodao, and we have some chinese polearms like the hafted blades and the tassled spear
But a jian would be very nice; short stabbing weapon