Scrappy Mechanic / Xenoblade Chronicles 2

• As opposed to previous Xenoblade entries allowing you to move while attacking (since some Arts require specific positioning in relation to the enemy), this game's auto-attack requires you to stand still. Plus your movement speed in battle is significantly slower than normal ^note Oddly enough, you can move at your normal speed while your Blade is performing a Special, mostly because your character isn't holding a weapon at the time.
• The game's tutorials leave a lot to be desired, from being overly vague on some topics to actively promoting bad habits and suboptimal playstyles for the game's combat, so much so that it's often considered a major reason for the game giving a bad first impression to a lot of players. Additionally, unlike the first installment, the game gives no option to read them again. The game attempts to mitigates this by letting you buy hints through Informants, but even those leave a lot unexplained.
• The gacha mechanic is... not good. The random appearance of Rare Blades is supposed to make every playthrough unique and exciting, and encourage you to plan strategy around your build. Instead it encourages the worst kind of mindless grinding and a "Catch and Release" style of play that goes completely against the stated themes of the story. It's even worse due to the fact that generic blades in sub-slots a lot of the time are better than using all rares, meaning players have to go through tons of Com Mons to get what they want.
• The map has a hard time showing exactly what vertical level of the area the player is on. The follow ball from X could have been helpful, or the multilayered map from 1.
• Rex's first common Blade will become all but useless as you progress, so it's very irritating that the game never allows you to release it. This is to ensure Rex can't end up with no blade during a certain part of the story, despite the fact that most players would have a dozen couple much better blades by this point. It's very annoying having an almost worthless blade constantly taking up a slot.
• A driver's default blade can not be disengaged for most of the game. This can seriously hinder your attempts to customize the driver's playstyle, since you can only choose two of their blades. New Game + averts this but requires you play through the game in the default way first.
• Field skills require constant party shuffling, which gets really irritating when there are several challenges in a row that require different skills. Same for collecting collectables and salvaging. This only becomes more annoying with higher level skill checks that require multiple blades with the right skill. This is mitigated once you get a lot of Field Skills on your team Blades leveled up (wherein you will often find you don't need to shuffle out party Blades at all), but this takes a lot of time and many players don't realize the benefits until they start struggling with field skill checks late in the game.
• Unlocking a Blade's Affinity Node requires you to actually visit their Affinity Chart to receive the bonus/allow progress on the next node. Forget to do that and you get nothing.
• When party members come and go at the beginning of a battle, it's impossible to tweak which Blades each Driver is paired up with at the moment, and it's also impossible to convert bonus Exp, skill points, and weapon points before being thrown into the fray. This often makes the first go at bosses far more difficult than it should be if your loadouts are underprepared for the fight.
• While the Blade Combo system is pretty fun, its implementation leaves a lot to be desired - not so much with how the game integrates it into combat, mind, but rather how it's presented to the player. For whatever reason, there is absolutely no way to look at the flowcharts for Blade Combo's in-game aside from activating combat and firing off a Blade Special. This makes building a team very tedious, since you either have to go out and get into random battles to look at the flowcharts, go online and look at the ones on the wiki, or just have them memorized. This is downright necessary for a lot of the superbosses as well, which often require a lot of strategy, certain sealing effects and certain teamcomps to beat.
• Aux Cores are a huge pain in the ass. In order to even use them, you have to refine them. In order to refine one, you have to go to a vendor and spend some resources to refine it. Don't have the resources? Better go find them. On top of that, there's no option to "bulk-refine" Aux Cores, so you have to do every. Single. One. Individually.
• The only way to acquire upgrades for Poppi is by playing Tiger! Tiger!, a retro themed arcade game. While it can be fun, you will have to put a huge amount of playtime into it to fully upgrade Poppi, which can make it become extremely repetitive. Fortunately, an update added the option to play on an easier mode with no penalty, and New Game Plus gives you the option to simply buy Poppi's upgrades instead.
• Changing a blade's assigned driver requires you to use an overdrive protocol. Only three of these can be found in the overworld, with the only ways to obtain more are to either max out a driver's affinity chart or release a 4-crown common blade with max affinity (and only the latter method is repeatable). This ends up making the overdrive protocol veer toward being Too Awesome to Use, and discourages players from experimenting with different driver/blade combinations. The DLC gives you ten anytime you want them, making them much more usable.