According to ettoday they only performed SEASONS together, no Who... Chinese version.
JJ Lin wrote a song for her called
The Gift! For those who don't know, JJ Lin writes music for lots of singers besides himself.
Is that song a collaboration?...
It's saying that Ayu broke into tears after listening to the demo. It's a difficult song to sing, but it's like a "gift from the sky".
Some pics in the link:
http://www.ettoday.net/news/20150215/468165.htm
EDIT: it's a collaboration indeed. They're going to film a PV together in Tokyo.
http://news.ltn.com.tw/news/entertai...ngnews/1235149