Oh man, a Bloodborne anime would no doubt be a gory mess to behold, but I'd be concerned about the story. Bloodborne's story is bonkers to say the least. Conveying that in an anime would be pretty hard. I guess they could do their own spin-off thing, like a story about another character there trying to survive the Church's hunts, but it'd still be tricky.
Then again, Japan anime does like to go straight down to crazy town a lot of the time, so it can be done.
Mass Effect already having an anime kind of makes it one that shouldn't have been on the list. I also don't see how a Shadow of the Colossus anime would work given that the game being a game is a fundamental part of the story. It just doesn't have a story that translates well to another medium. Xenoblade Chronicles X is a better candidate since its story is far easier to do such a medium translation, and that's just what I thought about off the top of my head (since I've been playing it today).
When adapting a game into a series, the first question one must ask is if it would even work. It's why most anime adaptations are of Light Novels instead of straight up video games, their stories lend themselves better to the medium.
All of Valenwood can be explored in ESO.
The Summerset Isles would work better as a single player video game IF it there was flight.
Beyond that I wouldn't trust plenty of anime companies with Kemono. I'd expect they'd do something more generic like Kemonomimi. Or worse where the males would be Kemono & the females would be Kemonomimi.
I'm surprised Final Fantasy isn't on that list. It already has plenty of the Tropes, and it's hard to shake the suspicion that they developers of the main titles seem like they'd be much happier making films then actual games. If the Spirits Within had been a success instead of an atomic grade bomb, I wonder if that's what would have ended up happening instead of "Hey, here's a very pretty tube. Walk through it for 40 hours while we make you watch unskippable cut-scenes and sit through insipid dialogue".
ON topic, I dont really see the point of converting Metal Gear Rising into an anime, it /already/ has the spectacle, and part of the fun is that you're the one that gets to suplex a Metal Gear and pull of loads of crazy swordplay, surely?
Elder Scrolls probably wouldn't work too well either, it's very, very western and I feel may clash horribly with some of the archtypes that are present in a LOT of anime. Nor would Shadow of the Collusus. It's entire mood comes from it being a game, a game with very little speaking.
I mean I know people love anime, but you need to take into account whether something would even work in a non game format to begin with. Also, why not just "animated" adaptations, why specifically anime? Is anime better for adaptations?
I see Psychonauts being better adapted into a stop-motion feature by Tim Burton than anime.
And it's redundant to adapt any Metal Gear game into something like a movie, because they already feel like movies anyway. Unless it's a story that's set in the same universe of the games, like what they're doing with Assassin's Creed.