I don't follow one super closely but I'll comment on the fighters I do know and follow.
Anatoly Malykhin - Heavyweight, potentially Light Heavyweight. If he were in the UFC he'd be top 10 easily at HW, maybe top 5/10 title contender but I am a little concerned about the size vs guys like Gane, Pav, Blaydes, N'Gannou and Aspinall but he'd mow down the rest most likely. At LHW he's easily a title contender, maybe champion.
Arjan Bhullar - top 10ish HW, cut above the fatties mostly but a cut below the elite.
Amir Aliakbari - Very similar to Bhullar in where I have him, clearly below the elite but good enough to he a top 10ish HW give or take a bit.
I don't know who's they got at LHW
Rainier De Ridder - At MW I think he's a to 10-15ish guy, nothing too special.
Roberto Soldic - He was the KSW Double champion, 27 years old 20-3 with a KO win over Dricus Du Plessis and a split decision loss to Yaroslav Amosov...Dudes elite, dynamic knockout artist, solid defensive wrestling, beast of an athlete. It's a shame the UFC is so cheap as they offered him less than KSW did to stay and considerably less than One offered Roberto...but hey, only the best in the UFC guys.
Saygid Izagakhamaev- Khabibs star WW, 22-2 and 28 years old. He came up short for the UFC contract vs Carlston Harris which is a shame as Harris is already 35, much more upside to Saygid who's very much UFC level and one of the better WW prospects out there. Smart move by One getting him.
Murad Ramazanov - Another one of the better Dagestani WW prospects, 12-0, absolute tank of a wrestler and only 27. Quality fighter who'd do just fine in the UFC.
Christian Lee - at only 24, dude is both of the best champions outside the UFC and one of the best prospects. He's all action and a top 10 caliber LW. Hopefully he returns to the sport.
Shamil Gasanov - at 13-0 and only 27, he's won a bunch of grappling tournaments in Russia and he trains alongside Islam Omarov who's also one of my top Russian 145ers. Shamil is very good, I was disappointed when I saw One signed him as I was hoping we'd see him in the UFC or Bellator. He's basically a shoe in for the FW title in ONE though, their division isn't too deep.
Fabricio Adrade - Only 25 and 9-2 in MMA but clearly a freak athlete and was a 20-3 Kickboxer (I've also heard his kickboxing record was 29-1 and like 40-3 so I'll go with the modest record). Andrade is a prospect in every sense of the world, hasn't fought a strong wrestler yet, shows suspect takedown defense vs other strikers at times and while his offensive striking is as dynamic as anyone's at 135lbs in MMA his defense is too open. That said, he's absolutely UFC caliber and at such a young age could really be a champion in any promotion one day with the right development.
John Lineker - Well he has wins over Chito Vera and Rob Font, both current top 10 guys but I do think Lineker is getting older and 45 pro fights into his career his best years are behind him but he's an iron channel slugger with big power who really has given a lot of people issues. To be fair he lost a split decision vs Sandhagen and won a narrow one vs Chito before leaving the UFC for missing weight for like the 5th time. Lineker is a guy who'd still give ranked fighters trouble and put on exciting fights but I also think he'd lose to a lot of up and comers too. Very UFC level still.
Mighty Mouse - At Flyweight he's the GOAT, he makes 500k a fight in ONE or thereabouts, I doubt he's coming back. I do wonder how he'd fair vs some of the top guys these days, I think he has a fair chance to beat Figgy and Moreno but I could also see him losing to a few of the best at 125 in the UFC, I think pushing 37 Mighty Mouse only has a couple left in him and is already out of his prime but...he was so elite he had prime to give up.
Adriano Moraes - Flyweight? But probably still Bantamweight in the UFC? Either way he's a quality fighter, at 125 in the UFC I think he'd reach top 10, at 135lbs I think he'd struggle but to reach that rank but would still do more than earn his roster rank. He's 34 now though and the shelf life at these weight classes is typically short.
Kairat Akhmetov - one of the first talents to come out of Kazakhstan in MMA, dude was solid and I wondered back in the day how he'd do in the UFC but that was like 10 years ago when he was an undefeated prospect. Now he's 35 and I honestly think he's a fine fighter but not much else to say at this stage in his career.
I'm sure I'm forgetting some guys but all in all, Ones Roster is very thin of top talent. I think in general with the grappling, muay thai and MMA they kinda spread themselves thin, they certainly aren't anywhere near the divisional and roster depth of Bellator but....they are willing to throw money down for marquee fighters and do pick up some good up and coming talent that other promotions would be happy to get as well. I'm sure I missed a few guys and I wouldn't mind hearing which ones.
