OP actually mentions "East Asia" specifically hence the 3 bracketed countries.
AZIN), just randomly found her music looking around sharing sites, nice light voice
Cool music. Didn't know this singer before.
Your username! (and avatar)... been some time since I've listened to Versailles. Absolutely loved them, but didn't find much time back then to explore their stuff. I still do have Serenade and Revenant Choir (studio as well as live), then some of the Hizaki's solo tracks in my playlist. If you wish then please recommend their songs which you like : )
IDK maybe you can try thanatos, created beauty, edge of the world. Honestly I think it is easier to recommend songs not to check out as I like almost all of their songs.
But I do recommend you try out Kamijo's solo material such as Heart and Symphony of the Vampire if you are into Revenant Choir
note: this is a 30 min song/video