I’ll chime in before the comments containing “If you have to ask, you’ll never know” pop up, I guess. First of all, I’d say you’ve - for the most part - answered your question already. You’re list contains most - if not all - of what you’ll actually require.
Initially, you’ll need an idea. That’s of course where it all begins. You’ll need a storyline, with a plot, characters and so forth. A massively multiplayer online game is rather complex and far-reaching. You need to keep players entertained for hundreds upon hundreds of hours. Otherwise, it’s really not going to work, is it? As such, this is where it starts. Once you have this, you can move on.
Next up, is putting the idea into motion. From what I can tell, you don’t have any experience with game development. This is a massive undertaking. Unless you plan to learn how to program, model, texture and animate yourself, then you’re going to need to hire people for this. That in itself is incredibly expensive. Especially considering the amount of assets and depth a MMO requires. Though, don’t get me wrong - it can be done. You’ll simply need the drive, time and money to do it. Most, realistically speaking, will bail rather quickly, though.
To be honest, some of what you’ve mentioned really isn’t important this early on. At this point, I wouldn’t worry about audio production or a website. That’s not super important at this early stage. You can worry about that much later. Similarly, I’m not sure how many “laws” you’d have to concern yourself with as of the moment. Unless you are considering basing the game on a storyline written by someone else - such as a popular movie or book, for example. Though, I doubt that’s what you’ll be doing here, anyway.
Eventually, if you develop the game and consider a subscription-based model (though, most MMO titles are actively moving away from this, and going free-to-play), then you’ll likely have to concern yourself with this more. People pay for a certain service, so you’d want to be legally secure, were you to no longer be able to provide it. However, again, I’d not even worry about this at such an early stage.
You will most definitely need servers. And, certainly, it would be wise to consider this infrastructure as early as possible. You’ll potentially need a large amount of them. That of course, ultimately depends on the success of your game, in part, though. It’s always good to be forward-thinking, though. This part, can be rather expensive, to say the least and you’ll want to do some research on that front if you’re serious.
I’m not sure what else to say, really. You’ve asked for essentially an overview. If there’s something more specific you’d like an answer on, I’ll be happy to assist. In the short, though, developing a game of this scale is possible. But, these kind of projects pop up all the time and almost always fail. Though, there are exceptions. They’re simply few and far between. If you have the money, which you’ve said “isn’t really an issue”, though, it is more than possible. Just don’t expect it to be a quick or easy journey.