I don't know if it's really an anime song? I mean, it's really good, but I don't think it's a "early 2010s anime song..."
Edit: I looked at the post on twitter about the 3 covers and it seems RAS and Yukina's cover will be out on December 27 while this one will be on December 26? I'm not sure, but maybe it means that this one is kind of a bonus cover.
Here is the preview
