Might as well add mine now:
Final Bout - I could basically just say "everything but the music/Opening visual" and it'd be correct, but I'll go with how overly complicated launching some special moves was.
Budokai - Pretty much everything about the combat. Things such as any special move that wasn't the Gyarikku Ho such as the Kamehameha and Death Beam having a chance to push the opponent back less than a standard Ki blast was stupid, as were things such as Freeza's transformations not being permanent.
Budokai 2 - It had too much of a give and take going on. Unlike the Tenkaichi games that would constantly expand the roster, this game took out Dodoria, Zarbon and #19 for no real reason when they still had combos and moves to work with for them. Not too bothered about the story mode when it offered something different and a good amount of variety in what characters could do, though some of the unlock conditions without the code were pretty weird such as that Gohan's Cell Arc self would only be unlocked by beating Cell in the final stage with Boo Arc Gohan.
Budokai 3 - The RNG is pretty bad in Dragon Arena with how break ins essential for unlocking 2 characters and the Cell Games is entirely random. Dragon Rushes are in a similar boat with the chances of them being successful or not being a pure gamble, especially frustrating when higher level CPU characters like to spam them at any opportunity.
Legacy of Goku - Pretty much everything beyond the models as already stated. The biggest problem is probably the ludo-narrative dissonance with how much grinding is essential. It's hard to imagine Galu as the world's strongest fighter at the time if he can get killed by some random wolf
.
Legacy of Goku 2 - As already said, the egg quest is overly annoying without enough trial and error to map out the best route and, again, shows the series' ludo-narrative dissonance with how your character can't just fly with it.
Supersonic Warriors 2 - As already stated, that one Broly challenge level was unbelievably broken with how his super attack will just fill up the whole screen. The tiering system was also one that showed a big case of power creep with how it'd make a lot of characters naturally weaker (eg. someone like Freeza or Ginyu having little chance of doing anything to Broly or SS3 Gotenks).
Shin Budokai - The game doesn't really offer much to do outside of story mode and arcade. The story itself also has a lot of dumb moments and power scaling issues as bad as an average Super episode too.
Shin Budokai 2 - A similar lack of content outside of story and arcade to its predecessor. Story was at least somewhat better, though things such as Gohan being the chosen one for the Z-Sword despite his feats accomplishing little in either timeline or Pure Boo suddenly becoming stronger than the main timeline Boos were because reasons were pretty bad (though I guess not as bad now we know he had God Ki all along
).
Super Dragon Ball Z - There's not much to do outside of arcade mode beyond messing around with some movesets and the general gameplay is very difficult to get accustomed to.
Tenkaichi/Sparking - The game's combat is very bare bones and broken, the only combos available being a gut punch, kiai or knocking the opponent back before a Dragon Homing attack, something very frustrating for naturally difficult levels such as Goku VS Oozaru Vegeta or SPC VS SS2 Gohan in the True Ultimate Android What-If. Exclusively for the English dub, there were also some very noticeable moments of laziness such as how SSJ Trunks' Finish Buster of SS4 Goku's win quote against SS4 Vegeta weren't dubbed at all.
Tenkaichi 2/Sparking Neo - The story mode is both the best and worst element of the game. Even though its length and scope is praise-worthy, there are some notable cases of padding within it such as Bardock fighting a bunch of Cui clones meant to be Dodoria's elite being separate from fighting Dodoria or adding in a fight with Tao Pai Pai to the start of the Boo Arc so that Great Saiyaman and Videl weren't just relegated to the movies. The handling of GT was also incredibly lazy with the Baby Arc starting about halfway through it and having an underwhelming ending to the Evil Dragons Arc that lacked any sense of repercussions or finality that even Budokai 3 was able to accomplish despite it only adapting GT through 1 fight in Goku's story mode.
Tenkaichi 3/Sparking Meteor - The heavy shortening of the story mode was a step down from BT2 despite the in battle dialogue and opening/ending cutscenes containing better story telling, with the exclusion of a lot of battles important to the story being fairly egregious. The random nature of what tournament difficulty would be available made unlocking certain characters like Lord :bitch or King Cold pretty annoying too.
Infinite World - The mini games that allowed it to stand out could also be the most frustrating part of it. Despite the length of the story mode, it's story telling was also very bare bones.
Burst Limit - Unlocking dramatic pieces was tedious when it required very specific outcomes.
Revenge of King Piccolo/Tenkaichi Daibouken - Some of the parts of the game were too tedious to justify their length such as filler battles of Karin sending Galu down below the tower or Goku fighting off creatures in Baba's palace. The 1 V 1 duels also have some overly basic mechanics when it comes to physical combos and the like.
Raging Blast - The inclusion/exclusion of certain story mode battles just for the sake of not adding more characters ended up being very stupid (Ultimate Gohan VS Boo not being in the game despite Ultimate Gohan being referenced in character bios, yet Piccolo training with himself or Galu and Vegeta fighting the copy warriors inside Boo are fine?).
Raging Blast 2 - A lot of the combos are still pretty basic outside of Raging Soul.
Ultimate Tenkaichi/Ultimate Blast - The gameplay is basically rock, paper scissors when it comes to combos and the giant bosses requires a ridiculous amount of button mashing for the QTEs.
Xenoverse and Xenoverse 2 - The RNG for unlocking both Ultimate Finish scenarios and certain unlockables from PQs is very frustrating when considering the effort you go through (though XV2 at least lessened that for the Ultimate Finishes) especially with how essential Blue Hurricane is in XV1 for later missions (think I needed to beat that level of defeating Freeza Soldiers over 10 times).
FighterZ - Unless you're capable of putting up with the sweatfest that is online (especially with ranked matches running on an Elo system), all you're left with is a bad fanfiction of a story mode with a repetitive structure.
Kakarot - There are quite a few noticeable retcons or just weird plot holes in general within some substories (Yamcha saving and meeting Pu-erh because he thought he heard a woman in distress despite his fear of pretty girls, Piccolo saying Goku would just eat the food in the Rosat at a time where Goku was dead and his friends presumed it to be permanently, etc.). Methods of obtaining Zeni quickly are also limited to just using the Dragon Balls.
somehow being winnable. Also, there's little to do other than the story mode and arcade as you said, though that's a common thing with a lot of DBZ games. Story mode is slightly less retarded than FighterZ's story mode though.
