I have to wonder if I can use the word "disappointing" to describe Battlefield V? Most people already considered it a travesty for a while now ... it will more so be meeting people's expectations rather than missing them, if anything. Confirmation bias. That being said ... I think you could still call it disappointing, from the perspective of "this could have been so great!"
Because so many (really ... most) of these games have the possibility to disappoint it's audience and critics, I'm going to segment them into different levels of disappointment.
Battlefield V: even though you could argue a technicality that this isn't really "disappointing", I think overall this kind of marks a point where all the good will towards Battlefield has finally more or less withered away. It doesn't disappoint me personally, because I've always found significant flaws with Battlefield, but I must admit I was hoping to give it a try this year ... now I have little interest.
Assassin's Creed Odyssey: Will Odyssey ruin all the good will built by it's predecessor? Maybe not completely, but for the most part, absolutely. Whereas I had a mild interest in Origins, I have none for Odyssey. I think people will still recognize the good in the major switching up of gameplay that Origins brought to the franchise, but that won't stop them from feeling tired. It's odd (heh) because I have not really seen resentment against Ubisoft for not learning their lesson ... more so sheer apathy. That's probably worse, honestly.
SoulCaliber VI: Fighting fans have put up with so much shit this generation that I almost want to put this in a lower category of disappointment just because it seems like (keep in mind I'm not 100% up to date with this game) the bare essentials of what makes SoulCalibur good are there. However, with so much anti-consumer practices relating to it's DLC, I expect a lot of bad press, lackluster interest from casuals, and middling reviews from fans and critics. People saw this announcement as the return of an era, which seems to be true for the reveal of any fighting game nowadays ... expectations were very high. Even if this doesn't disappoint critically, it will most likely sales wise, if not for it's negative press than for it's crowded release schedule.
Pokemon Let's Go: One of the strange cases where a fanbase which has every capability of being rabid and cynical has .... actually accepted what a game is going to be, and that it may not be for them? Still, I think that a lot of people will be disappointed in the mere existence of it, and the quality will definitely be lower than that of past Pokemon titles. If this "core" spin-off continues as it's own series, I actually think people will become more disappointed over time.
Fallout 76: Even more so than Pokemon Let's Go, I'm honestly surprised at how mature most of the community is being about the departure from the main game. Whereas that game will probably get very little acclaim though and won't appeal to hardcore gamers, I expect 76 to do well in both attracting a new audience and gaining support from big name sites. Honestly though ... I don't even really know what this game is besides being a multiplayer Fallout. Seems to me like the concept wasn't explained very well. This is the game that I'm the most likely to be wrong about.
Hitman 2: Even if this ends up having the best mission design in the Hitman series, the glitches, bugs, and online DRM (which will most likely affect certain parts of the game but not all of them) are setting it up for some beatings. It will almost certainly have mediocre sales.
Super Mario Party: Will pretty much be the new Mario Tennis Aces, a game which people were hoping was excellent only to find out that it was just a good return to form. Although this game does have lower hype than Aces, which if anything will help it in the long run.
Just Cause 4: Stagnation. But it knows what it is.
As for games that will have almost no disappointment whatsoever ... Forza Horizon 4, Mega Man 11, Call of Duty: Black Ops 4 (surprisingly), Red Dead Redemption 2, and Smash Bros. Ultimate. That's not to say no one will be disappointed, but that their target audience and critics will most likely have their expectations met. Sales will also be what the publishers were probably anticipating. I almost put Mega Man 11 into the mildly disappointing category, because a lot of casuals probably won't get it, and some fans have crazy expectations. But that's not really fair ... that's just Mega Man.