This is an ambitious concept. Could it be done as freeware, or as an independent game? I don't know... Think about how easy or difficult it would be to program. Think about what programs and programming languages you would need to understand. If you have a vision of what your ideal game would be like, and you believe it could be created without too much frustration, then start creating it. Sentou Gakuen
is a free browser MMO that's also considered an online visual novel. It is likely different from what the game that you want to create, but it might provide a good example of what can be done.
Please be aware that ambitious games have a tendency to get stalled in the middle of development. Especially if you can not charge money for the final product. If you don't have a lot of time, passion, and dedication, then it's very common for development to be put on hold. Jobs, illness, stress, and life commitments get in the way. It's difficult to get a game or VN finished on one's own. Trying to get a team to work together can be even tougher.