The original song of "Blowing to Dream of Xizhou" is Huang Shi Fu and Yao Yang, and the name of the song is taken from "Xizhou Qu", "The south wind knows what I want and blows to dream of Xizhou". Although this song is not a cover from a Japanese song, there is an officially authorized Japanese version. As for the specific copyright issue, I can't provide detailed information.
if you have questions about copyright or need further help, please consult a professional legal person or relevant institutions.