>>104683997They are possible, but not practical.
There are 2 ways to try and go about it. The first is just to get the original talent. This is possible, but very unlikely, because there is usually a reason for someone leaving a company. The company would have to fix the issue and give a better reason to rejoin the company than to get what they had back (Plus, isn't always an option, either because they're a liability to the company due to leaking information, physically unable to perform the role, or are just dead)
The other is to replace the person behind the model. That is not realistic, except for in the far, far future. Vtubers aren't like voice actors, where they just need a script or character synopsis and a close-enough voice. A large portion of the content requires, effectively, an entire IRL human's background, and replacing that is going to cause contradictions because "During this members' stream, they said XY, but in there most recent stream they said Z, which is mutually exclusive," or a much simpler "they don't act like this, this is clearly someone pretending to be them based off of the highlights." This still applies to AI, as well as needing to remember every single interaction that was made for a year at least (to not cause contradictions with itself) and won't accidentally break and cause an obvious AI issue (An AI breaking down and spreading slurs is funny content when you know it's an AI, but is terrible if you think it's a person and they suddenly say something that is both not allowed by the company, and the original person would never say.)
