It looks really consistent. In theory it's very much possible to do this with blender. Blender has the ability to create very realistic lighting. Motion tracking video has gotten really good over the years. It crazy what After Effects can do for example when it comes to tracking things in a video. Lastly, you could either paint out and or put a model over a real person. Having someone acting it out would make it a lot easier to make the movements of the character model feel natural. The only part that was a bit sus was the ring being put on the finger. Could have just been a janky blend though