Kaido can beat any admiral in a one on one by in verse logic, but two or three beat him 10/10. Katakuri isn't adding anything of note that marco didn't, Except being taken out even faster.
Add big mom and it's a close battle. The WB pirates all seemed above average for a yonko crew, Marco exchanged blows with admirals, yet both big mom and kaido have one shot other commanders. Marco was also enough to give black beard yonko status after marco was beaten...
Without amai mask i feel the hero's don't have enough power. Adding him would make it feel unfair against the mha team though. Nobody in mha is above demon lvl bar gigantomachia, twice(depending on who he copies), and the users of OfA/AfO currently.
@dimitri1220: that would increase their odds, although that also means that the two strongest nnt members can't help take aizen down. If galand goes down before ks is put up aizen might solo them with it, as he would be the only counter to ks left. If aizen is teleported first, greyroad can block teleportation with a magic ability he has, also resulting in a ft losing the majority. If aizen is teleported with the dk and zel, than ft also loses that three way.
Aizen realistically has to go down before the teleportation, and they only get to use teleportation once thanks to greyroad. That requires Jacob or August surviving long enough to do so while every other inch of the battlefield is covered in multi mountain-island lvl attacks.
An argument could also be made in regards to dk and zel vs the ft team. Purgatory storm can one shot everyone that relies on air to start the fight, and zel is immune to crossfire unless the dk explicitly desires otherwise. Zeref will get his curse removed, losing his best hax setup. Zeldris being immune to magic along with having regen/immortality negation, ominus nebula, and even on contact magic sealing makes him able to take nearly anyone in a one v one.
That leaves at best a handful, and it's doubtful that the stragglers can take the demon king, especially when the ruler is around. All magic damage is turned into healing and vice versa, turned on or off by thought.
@dimitri1220: yeah, it should go to fairy tail team unless brandish gets targeted quickly, then it could go either way. Bloodman could also die to greyroad's hax if he lands a kill shot while time is flowing. Ft 7/10
The demon king has specifically removed the ability of characters to die, Those characters couldn't die, period. Even immortality and regen ignoring attacks still couldn't keep them dead. Normally I would also question someone's ability to remove such a strong curse, but the demon king has specifically dealt with that exact type of curse. It's fair game, and the term god is vague, the demon king and his rival beat and sealed his god that created the world and was a reality warper.
Giant versions could be a problem, but they will still die to the same hax, so stepping on someone accidentally is a death sentence on the spot.
Aizen has a few counters.
Tricking the commandments will trigger the "thou shall not lie", resulting in aizen turning to stone. The sins tricked galand, and only merlins prep and curse negation saved her. Since she's frozen in time, it also bypasses fairy tail's time stop.
Zeldris could just ignore it and possibly solo him, although he might not be enough alone.
Estarossa at his most powerful had an ability that canceled telepathy based abilities, making ks useless. That was after absorbing the third commandment.