Joyoland has posted Ys Memories of Celceta, Ys Seven, Zero no Kiseki, and Ao no Kiseki to Steam Greenlight. Joyoland is the developer of the Chinese ports of these titles. From the descriptions, these are all in both Simplified Chinese and Traditional Chinese.
You can find Joyoland’s steam listing here.
UPDATE
Edited: 3:25pm Central Time, 1/5/2017
I’ve got a bit more information on this, thanks to BigKitten‘s posts on the Reddit thread.
First in a response to one of my comments:
This is from their official weibo (Chinese twitter knock-off) (http://www.weibo.com/1821444155/EpriiaW2D) and wechat (http://mp.weixin.qq.com/s/iEteeoZDe0fTnjXv7sA7Mw):
北京欢乐百世科技有限公司宣布。
自2011年至2015年，代理移植至PC平台的四款日本falcom公司的游戏作品。
零之轨迹、伊苏7、碧之轨迹、伊苏树海确定将会登陆steam平台。
于今日正式开启了登陆steam平台前的青睐之光投票活动，欢迎广大falcom游戏fan与游戏爱好者们积极投票，争取早日让这些作品在steam平台中各位见面。
Rough translation:
Joyoland announces:
From 2011 to 2015, the four Falcom games published and ported to PC [by Joyoland] – Zero no Kiseki, Ys 7, Ao no Kiseki, Ys MoC – are confirmed to be released on Steam.
[The company] starts the greenlight process today. Fans, please vote to speed up the release on Steam.
So, my understanding is: they are determined to release those games on Steam already.
And from another comment in the thread:
The following is what I have read in the Chinese forums. Take it with a grain of salt:
The head of Joyoland is a reasonably good associate of Toshihiro Kondo, the head of Falcom and they have collaborated for more than ten years.
Joyoland has full publishing rights to Ao and Zero in the greater China region (mainland China, Taiwan, Hong Kong, etc.).
It is not beyond imagination that they may procure publishing rights in other regions. Joyoland was to publish their PC port of Ys in the west (http://www.esterior.net/2013/04/pc-version-of-ys-seven-in-english/). It was only canceled because Ys sold so poorly in China that Joyoland deemed western releases a risky venture.
So…if they sell well on Steam……(well, I guess I am dreaming..)
Thanks for the additional information!