I agree. It's weird to go into a match and you see Khabib using the same leg kick animations as your Barboza. It's one of those things that's jarring to look at and prevents the game from resembling real MMA from afar in the same way that a good NBA game can.
If I had to break it down, I'd say there are a few things holding the game back from truly looking like the real deal:
-Not enough bad/mediocre animation sets
-Not enough "signature" animation sets (Cro Cop has same head kick as everyone else)
-Outcomes of knockdowns and ground scrambles are too limited in scope, leading to these situations feeling inorganic
-Blocking animations take fighters out of their signature stances, removing a large element of fighter aesthetic (this is one that Martial and I have talked about a lot - he believes that the far-non-blocking animation is what it should look like to not block at all, and the close idles are what blocking should look like, and I agree)
-Kick / punch power being tied together leads to an inauthentic in-game presentation. Conor has crazy punch power. Accurate. Then he throws a rear leg kick with the same force (or close to Barboza) and snaps the leg back of the opponent. Inaccurate. This matters in terms of gameplay but also aesthetic, because his unrealistic kick power affects the reactions of the opponent in an unrealistic looking way.
-Everyone having the same head movement style looks inauthentic. Anderson moves his head with the same animation as Khabib, lol. This is something I feel like FNC got right, but it helped because characters could block while slipping and had signature block stances. So a Tyson peekaboo slip looked nothing like a hands down Ali slip, which looked nothing like a Foreman mummy slip.
-Fighter tics and idles need some sprucing up. In real life you often see fighters doing little micro-feints, reaching out to hand fight (which could maybe be an actual mechanic), walking into range (like with a slow, realistic cadence). Sometimes they'll push a palm into a glove to make sure the glove is on tight. When Anderson was in the zone and planting during head movement, he'd sort of bounce on his heels. These little micro-mannerisms are missing or just very muted. These are the things that make fighters look like actual feeling humans and not robots / mannequins.
-In the game, fighters' faces wince really hard in pain. In real life, you only see that kind of wincing from groin strikes or liver shots. Go into practice mode and just punch Nick or Nate Diaz in the head and pay attention to their faces. They look like goblins. Like they stop even looking like Nate and Nick, who are stone faced killers. The game's facial animation system is overblown, and it makes fighters look like they've lost composure when hit. A slight grimace or narrowing of the eyes is fine, but these guys in-game look like you hooked up electric nipple clamps to them and cranked the juice to 1000 volts. It's absurd.
As an example, here is a picture of a fighter I took during the beta. Who is this fighter?
If you guessed Baraka from Mortal Kombat, you would be wrong. That is Eddie Alvarez. Looking nothing like Eddie Alvarez. Baraka for comparison:
-When getting KO'd the fighters all close their eyes gently and look like they're taking a nice little afternoon nap. In the actual UFC, one of the grislier aspects of KO's is that the eyes often stay open. The lights are on but nobody's home. I won't post the pics (because why), but who can forget Shadface.jpg? Who can forget Machida's face after he was choked out by Jones? Overeem lying in a slump after Ngannou? Maybe I'm just a barbarian but it completely kills my immersion to KO someone, and instead of seeing them stiffen up and twitch with their eyes rolled back, it looks like I just read them a bedtime story and gave them a nice kiss on the forehead before their first day of school.
Anyway, I definitely agree with Martial's post, just giving my 2 cents on the state of visual immersion in-game and how it could be improved.