"The name's Hakurei Reimu! Shrine Maiden! Guardian of the Hakurei Barr — oh, right, I lost my Guardian position to Sanae. But that doesn't stop me from burnin' this place to the ground!"
If that's Rei, then why is she so tall? Seems like the ghost of Yui following Shinji around outside Unit 01.
Either it's a tic of the reference photo, or it IS indeed Yui considering the figure is apparently supposed to be the ghost one of the character's mother in the original scene.
Hopefully, considering that she got Final AttackRide-ed and then slashed in half so hard she exploded, Beatrice didn't survive for Golconde to grab her.
A minor detail I like is that the sword is only glowing in three of the images, as if Fi expects she’ll be needed during those eras, while asleep/inert before OoT and WW.