"Spam nonsense" me? Lmao, you mustn't have read all the other 1k word essays I've wrote on various threads concerning the pros/cons of certain classes.
Karma Majin: As for Karma Majin, as Horrid said it's the Ultimate's advantage. The Ultimate could quite literally go full dex against a full focus/prop Karma, and they'd tank them the entire time; If Karma misses a single CC the Ultimate's given an opportunity to get a couple hits on the Karma. If the Karma somehow manages to land EVERY single CC, then they'll be forced to win via Dice. This wouldn't be the case if confuse resist% didn't damn near guarantee a confusion resist. And unfortunately that's not all, for some darned reason confuse resist% also decreases petrification duration.
Swordsmen/Fighter: If the Ultimate Majin doesn't use autopot, senzu bean, or any of their LP items, then MAYBE a plus 15 SM can kill Skedar; But just like Fighter, they won't accomplish anything 9/10 times. The best strategy a Swordsmen can use against Ultimate Majin is full focus/CD, assuming they somehow manage to survive a Ultimate's barrage of attacks(which won't be often considering they'd be wearing Focus), they can attempt to continuously spam their stuns/KDs until the Ulti is knocked out. However KDing players out nowadays is really iffy, for some reason certain players can just jump back in the arena as they please after being knocked out. Killing a Ultimate Majin who's wearing an entire physical defense set even with full props is unrealistic with the game's current state. I've got a plus 14 SM acquintance who wasn't able to do anything against Skedar in terms of dealing a single health bar. I won't bother making a separate paragraph for Fighter, I'm sure just about anyone can agree that Thunder/Needles will NEVER come close to killing a Ultimate Majin. I'm not sure if you're aware of this, a plus 14 Fighter fought Skedar, and he won via heals and reflect(didn't even bother to attack the guy).
Dark Warrior/Plasma Majin: Dark warriors can't exactly kill Ultimate Majins, and since the recent arm pull nerf they've been rendered useless against Ultimate Majin. They'd stand a chance if it was possible to land confusion, but as I stated previously that won't happen with confuse resist%. Same can be said about Plasma Majins, at best they can try to KD them out; However when all your CCs are rendered useless, and with KDing out being weird.... Enough said.
Turtle Hermits: To be honest, there's not much I CAN say about Turtle Hermits; They're kind of an enigma for me in terms of fighting Ultimates. IN theory they should be able to put up a good fight against Ultimate Majins, however Skedar managed to 3-0 arguably the best Turtle in the entire game. In terms of killing the Ultimate Majin, that's obviously not an option. I know it's going to sound iffy when I say this, but I don't believe Turtle can kill Prop Ulti; and before you try to call me an idiot who's spouting nonsense, hear me out. If Karma Majin can't manage to kill a dex Ulti, despite them being able to damage the Ulti THROUGHOUT the match(Turtle can't damage Ulti while they're sleeping), I don't believe a Turtle can do anything against a Prop Ultimate Majin. It's really just a matter of Ultimate Majin waiting to resist/dodge to get an opening against the Ulti. It's the same scenario with Karma Majin, they have to win via Dice, and if they're not lucky the Ulti gets an opening to attack them.
Shadow Knights: Listen, as an ex-Ultimate Majin your strategy will most certainly not work. Even if you're smart about your debuffs, the Ultimate Majin will be able to remove them almost instantly if they've have the slightest hint of "skill" in this game. They can just about counter any Bold Strike that comes from the SK via paralysis/bleed removal + heal. A better strategy would be to spam taunt debuffs with full focus and CD accessories, and THEN use curse/life steal; That way you're simultaneously nerfing their damage somewhat, and keeping them from removing your debuffs. However, although it's possible to kill a Ultimate Majin with plus 15 crafted armor with this strategy, it's very difficult to kill one using CC90 armor. And that's assuming the Ultimate Majin wearing CC90 armor doesn't use senzu/autopot. Dealing with 3 UM health bars, when Ulti has the most props, lp% in the entire game, and one of the highest amounts of defense; It's just not going to happen. It'd be a miracle if you managed to lower their health 1 or 2 bars in 2-3 minutes, but the 3rd just won't happen. A prop SK does hardly any damage, a CD/Focus SK won't accomplish much except for lose more health(SK loses health not Ulti), then there's their obnoxious resist. Best they can do is win via dice, if they're not dead by the end of the match. Life steal was essentially their breadwinner when it came to damaging, but that's been nerfed so they've got nothing to offer against Ulti. You can try to argue that with more DoT debuffs, thus they can win via health. However if they time their senzu perfectly, it's null and void.
Crane Hermit: Well they can by multiple means, none of which are effective against a fully geared Ultimate Majin. One strategy is they can try to sleep lock the Ultimate Majin throughout the entire fight(If they manage to land all their hypnosis') to win by dice, another is they can try to by KD. Winning by KD against Ultimate Majin is very unlikely to occur, in addition to their resist, they can also remove debuffs making it very difficult to accomplish(If anyone's actually managed to accomplish that). If the Ultimate Majin wanted to, they could wear full anti bleed, and burn defense on their Eng set to nearly nullify the Crane's damage. Then the Crane Hermit is forced to spend RP balls on their burn in addition to the already costly KD spam. If they Crane Hermit tries to TS them, they can quickly switch to their Con set(if needed) in order to survive. Of course going with the defensive strat would make it "difficult" to kill the Crane, but I'd argue it's somewhat in the Ultimate Majins favor. The Ultimate Majin has the option of switching to anti-Crane damage gear in order to control the match so that they win by dice, but Cranes can do the same, so they're just about even in that regard. But if the Crane screws up one of their KDs, or CCs it allows the Ultimate Majin to land a possibly fatal blow on the full focus/CD Human. In terms of controlling the match it's a battle of mind games between Crane and Ulti, however Ultimate has the defensive advantage over Crane.
When it comes to Grand/Poko, and Dende I pretty much agree with you. I've heard rumors that skilled Dendes like DrMed can kill SKs with ease, and possibly even Ultimate Majins; But those are just rumors, and naturally the Dende has to have better gear than the Ulti.