Welcome back to Rate Their Chances in the wrong thread, where the rules are made up and the points don't matter.
I want y'all to just humor me for a moment. Don't give me any generic "oh maybe a character from [x] company or [y] game".
Quote this post, and tell me who you, personally, believe the 5th Fighter's Pass character is gonna be.
I'm currently considering three scenarios at the moment.
Scenarios one and two are what I'm personally calling "The Most Likely Outcome", and two characters fit this bill in my opinion: 2B, and Phoenix Wright.
2B has grown in popularity and has even already had a major crossover via SoulCalibur. On top of her ever growing popularity, Nintendo has had a great working relationship with both Platinum Games and Square Enix lately, which I imagine ease negotiations considerably. Her inclusion would be a popular choice, and she fits very well with the current Smash cast, bringing in another very unique, new world from which to draw content from. I personally think 2B has a 65% of being FP5.
Phoenix Wright is probably the safest of these two. His series for the longest time was a Nintendo exclusive and he is practically an icon of the DS era. He has a huge legacy among the Capcom greats and is a perfect choice for another Capcom character. He already has moveset potential via MVC3 as well, showing that he can indeed work in a fighting game. Capcom getting more characters seems like an inevitable thing to me given how crossover happy the company is with any project they're involved in, and Ace Attorney is, in my opinion, the most logical choice for a Nintendo crossover with RE out of the running. I think Phoenix has a 85% of being FP5.
Now, the third scenario I think could happen is what I'm viewing as "The Curve Ball Scenario": Reimu, from the Touhou Project.
Touhou is niche, yes, but it isn't
exactly unheard of. If you've partaken in anime and manga culture, you've almost undoubtedly come across Touhou at some point, whether you've realized it or not. It's often either undersold or oversold in popularity, but it is by no means the absolute no name that people are making it out to be, and is slowly but surely starting to gain some traction over here with spin-offs and mainlines making their way over for official purchase at last. Touhou appearing in Smash
could be just the thing it needs to really propel it, and the franchise easily has an incredible legacy to it that lead to it being an inspiration for games that went on to be big (Undertale being the most notable). Reimu fits the left-field pick that Smash seems to be oh so fond if, especially for it's finale characters. If Sakurai wants to keep us on out toes and really wow us with an incredible, never ever moment just like he did with Joker, Reimu fits the bill. I personally give her a chance of 40%, as most of this is admittedly wishful thinking on my part.