I never said he wasn't capable of handling multiple opponents at once. I specifically said he's never 2v1'ed two opponents of this caliber. Again Filloni originally intended Maul to be the one to fight Vader on malachor so we know he's already written with the intent of being an obstacle for Vader and has the feats to back it up, Ashoka wasn't far behind Season 7 Maul in terms of fighting prowess.
2v1'ing Ezra and Kanan (sub knight tier fodders) doesn't at prove that he has the speed/skill to take on some of the best of the era. Losing to Kirak is again...nigh worthless because Vader lost badly (with context) and only beat him because he threw the fight. Eeth Koth and some random Sith Lord managed to give him a challenge in the same comic run
Plus, ROTJ Vader has greater feats than both
I have no idea how you can accuse me of downplay and then bring this up. If we assume he used telekinesis like I think you're implying its Dozens of times better then his best showings by far. In the 2015 run he struggled with an enhanced rancor and even in the run where he fought that Kaiju above he needed the aid of that horse to fly him up into his face. Both showings he straight up couldn't beat them with just the force. If you want downplay I can bring up Palpatine's imperial guards tagging him 2v1 but that's obviously not the level he's consistently written to be at.
I can't be downplaying when I'm listing all of his impressive dueling feats...like literally:
https://imgur.com/a/yVHLO9k -- Vader vs Karbin (2015), Vader states on panel that he's being delayed by him and needs Aphra to shorten the fight
Based on these I would assume he would struggle with Maul, tossing in another equally agile opponent who's not far behind overall would best him.
Two people aren't going to overwhelm him just because of numbers, that's illogical.
That is how fights work, so actually yes. Throwing in another fighter completely changes the fight dynamic, now he has to block simetenous strikes from two opponents at once - both having superior agility, comparable speed with one of them not being far behind at all in dueling prowess and another not far behind that one.
Kirak sent him flying off the cliff. That wasn't Vaders fault but it's not a good showing either. He killed him cuz Kiran let down his guard down entirely and was focused on saving the town. Not sure what you're trying to imply by saying he was the strongest Jedi he had faced. At best you can use that and say he was better then Obi Wan but he'd lose to this duo as well, quite hard.
Dismissing the feats doesn't exactly help your case. I literally listed most of his good dueling feats - the only other significant opponent he had faced were the Grand Inquistor (unimpressive), Ben Kenobi who literally threw the fight and Luke who relies on scaling from Vader to be impressive. Ezra and Kanan are another duo he fought but they aren't worth mentioning for obvious reasons.
It was never implied he was unstable or weaker then usual I don't know what gave off that vibe. If anything he was more motivated then his usual self.
Vader never fought multiple cyborgs (sans the twins) at once. The showcase in Episode #6. Each Cyborg had a limited showcase with Vader before Palpatine said next and the previous fighter(s) backed off - after that it was battle royal and Vader was clearly only fighting the tradoshan (idk how to spell it)
The only two cyborgs he fought more then one at a time were the twins and they made him struggle. He lacks 2v1 feats to beat these two in sabers, much less dominate. By writer intent and his other dueling feats Maul would be a challenge, add in Ashoka and I can't see him winning.
Both of them while less technically skilled do possess a significant mobility/agility advantage on him and Vader has only one saber which does make it more difficult to parry attacks from two different opponents.
Filloni said it as well. I crossed it out, cuz it was a joke. Vader was at the peak of his grief and barely held him on the wall for a page before it was overpowered. I don't know why this is brought up to imply they're comparable.
His first canon series (very close to ROTJ) he struggled with two of the cyborg twins. Karbin who was a slightly tuned up version of Grevious was successfully stalling him and he needed Aphra to shorten the fight. In Rebels Ashoka at her prime staved him off, Maul would have been written to do the same. In Vol. 2 Eeth Koth had an extended fight with him.
Ashoka wasn't far off from Maul clearly
Hed pwn either one on one but he doesn't have the feats to handle a 2v1, especially in pure sabers.