As someone who knows an okay amount about how theme parks are run and a more-than-healthy obsession with Nintendo, I thought I'd throw my two cents in about what could or couldn't be on the table for Nintendo developments at Epic and elsewhere. I tried to be as realistic and objective as possible. I based the franchises I considered for this list on the ones from Smash Bros, as those tend to be the most popular characters/series Nintendo has to offer.
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S-Tier: Mario and Pokemon. Nothing else they own can come close to the recognizability of these two. The only slight nag with Pokemon is that while it is widely considered a Nintendo franchise, it also requires input from TPC. Jumping around any potential rights issues however, these should have no problem getting into the parks and making great lands.
A-Tier: Zelda, Luigi's Mansion, and Donkey Kong Arcade+Country. DKC would be B or C tier but gets the boost because of people's knowledge of the arcade game, the connection to Mario, and just how solid of an idea Mine Kart Madness is. A DKC subland is perfectly reasonable. Luigi is just more Mario, as well as being a solid ride idea. Zelda has always been a bit more niche than Mario, but is still one of the biggest and most recognizable gaming franchises out there. It might take longer than A-Tier but I don't doubt these will all be implemented somewhere in a big way.
B-Tier: Kirby, Animal Crossing. Recognizable and popular, but not nearly as much as S-Tier or Zelda. Kirby seems like the next thing after the Big 3, but I don't see a full land coming. Maybe a few off-the-shelf kiddy attractions and a Meet and Greet, but I suspect Universal will throw the bone to Illumination/Dreamworks before either of these get in. That said, a
lot of merch will be sold of these, and they will probably be really popular M&G attractions if implemented.
C-Tier: Nothing really comes to mind. Most Nintendo franchises are either very popular or incredibly core and niche.
D-Tier: Metroid, Star Fox, Splatoon, Pikmin. Not popular/recognizable enough at all to justify a full land/ride over others but with just enough niche popularity to point them out above F-tier franchises. You might see a little bit of merch of these IPs, specifically Pikmin/Splatoon. I would be very surprised to see a Samus M&G.
F-Tier: Punch-Out!!, F-Zero, Mother, Xenoblade, Game & Watch, Fire Emblem, Kid Icarus. Incredibly niche and/or aging properties that often require longterm commitment with the game/series to have proper understanding of the IP. Very little to no icon status. You could make a wonderful BTTF-style ride based off of Kid Icarus or a really cool dinner-theatre experience with Punch-Out!!, but the audience is minimal and returns will be small. Merch will be nonexistant outside of trace references to the Wii, NES, and Game and Watch devices. If Samus doesn't get a M&G, what chance does Captain Falcon, Pit, Ness, or Shulk have?
A wierd space for Nintendo franchises, are the Mario adjacent properties like Yoshi's Island, Luigi's Mansion, Mario & Luigi/Paper Mario, and WarioWare.
DKC only gets the boost to Subland based off of Donkey Kong's inherent popularity and the neccesity for the Subland to be Country in order to house MKM.
Luigi's Mansion has the same artstyle as the Super Mario games and is a part of the main canon in a way that the other sub-Mario's simply aren't. It's much easier to seamlessly add on Luigi's Mansion to a Mario land than it would be to add Yoshi's Island or Paper Mario. Not to mention that LM has elements of Haunt attractions and Shooter attractions, both of which have been amusement park staples for decades.
Yoshi's Island and WarioWare don't have the Icon status of DK or the ease of planning that Luigi does. I expect elements of Yoshi's Island to show up in the SNW Yoshi ride (Yoshi's singing, multicolored Yoshi's and Eggs, maybe even a Kamek at some point.) but the various artstyles and Baby characters/Yoshi-specific enemies like Raven or Burt the Bashful will not appear. WarioWare will not appear at all. It is completely divorced from the Mario series outside of the Big Wah in question and is too niche and not condusive enough to be given full theme park treatment. Same goes for the RPGs. Of course elements will be shared between SNW and the RPGs, as that tends to happen when both are based off the same main series. But any RPG specific characters, worlds, or artstyles just don't make sense to appear at all. Any merch of these series will be filed under Super Mario, and I doubt any characters or items exclusive to these sub-genres will end up getting spotlight. Sorry Fawful and Jimmy T fans.
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Those are just my thoughts though, I'd love to hear yalls opinion on the matter of Nintendo content. I'd love just about any Nintendo franchise to make the cut, I've been dreaming of a full Nintendo theme park since I was a kid. But sometimes I just gotta admit that Earthbound probably isn't gonna be getting a Hagrid's-style dark ride coaster or nothing.
If I want to guess at the lineup for Epic Universe, it will probably end up being SNW+DKC at launch, and two expansions being Pokemon and Luigi's Mansion in the coming years. Zelda will get thrown to IoA, and maybe some Kirby/Animal Crossing M&G/flat rides in Studios if we're lucky. I wouldn't count out Nintendo World Store Orlando in CityWalk either.
