(This is eng so hopefully you have an EN to JP friend that can translate this) But this (The original release of the concert and production) was originally all kinda thrown together like last second if I'm remembering right. I think if I remember from some of the notes Selen kinda said about creating this concert was that some parts (IE This performance in particular.) had been essentially vertically sliced and then smooshed together. And then harmonized. Meaning the parts that are all in sync were done probably all together and the parts not in sync like Petra's arms and choreography was cause she probably was doing her bit individually. Probably a similar case to Rosemi as they were uniquely very close with Selen. As for Petra and Rosemi's parts maybe being slightly different is these were their best takes on their audio unique parts and during the final edits what we have is what worked best between what was being said and what needed to be animated. An important concept when it comes to production is that not everything has to be perfect so long as it fits the energy of the scene.
