This was a fantastic novel! There's quite a lot to like here, but what kept me coming back to this novel more than anything else was the main cast, and especially their chemistry. I had a huge smile on my face pretty much any time Elisabeth, Marie, Finley, and/or Diana were interacting with each other. They were all fantastic characters in their own right, of course, and the way they developed together was a joy to read. Definitely a highlight.
I enjoyed when the story was comedic or heartwarming, but this story is more than capable of being moving, and sometimes emotionally devastating. My favorite chapters, a few near the end, were also some of the hardest to read. The author did a fantastic job of making us empathize with the main character, which made the story's most dramatic moments hit that much harder. Really impressive work.
The worldbuilding, too, was quite engaging. I grew to love Andraste, and it was especially strong as a contrast to Lumineuse. Scenes where we learned more about the world could have potentially ended up feeling dry, but they never did, and I never grew tired of them. The story even used its status as an isekai to great effect, too, which is something I almost never expect to say.
I really loved I Got Reincarnated as My Own VTuber (The title is one of the very few things I didn't particularly like, although that's more of a personal preference thing,) and would wholeheartedly recommend it to anyone.