The King has Lydia in the air by her neck, then throws her forward, through an office window. The surroundings, office, and window are all different when she is thrown than they are before.
In the final fight scene, the second henchman tasered by Emily is the tall one, but when that happens, the next shot shows a different henchman hitting the wall (that one, with the bald head, was the first one tasered and already on the ground) while the tall one is still standing there before getting tasered inn the butt (for the second time) and dropping.
When The King throws Lydia through the window and into the office, both office blinds are closed, but in the next scene showing them fighting in the office to the left of that one, you can still see the office she was thrown into, but the blinds on the left window are now open.
When Lydia is sending a text to Emily about the reunion, the name Emily's cell number is saved in her phone as "Emily Stanton", but when she reads Emily's response the name in her phone has changed to "Emily".
In the final fight scene as Laser hits Emily with electricity, Emily's left arm with the taser was extended, but in the next shot her right arm was extended and the left hand with the taser in it was in close to her torso.
When Lydia is trying to come up with a team name, she says "You don't say *mumbles* the 1985 Chicago Bears. You say *forcefully* in 1985 the Chicago Bears won the Super Bowl and created one of the best albums slash singles ever!".
In reality the Same Fransisco 49'ers won the 1985 Super Bowl, and the Chicago Bears won the Super Bowl in 1986.
In the liquor store, Emily held the taser on its highest setting to Kenny's face for a long time, but he got up after a few seconds and hustled out of the store, but in the final fight scene, she barely zapped the other henchmen (through their clothes) for maybe one second, and they were knocked out for the rest of the movie.
On "Training Day 2", Lydia wakes up and her nails had grown at least an inch overnight, but surprisingly the black nail polish also expanded to cover the new growth.
On "Training Day 2", Lydia receives injections in her chest because the injections have to go "through the boobs and into the pectoral muscle", but with her clothes an and the size of her boobs, the needles didn't even get close to going far enough to reach her pectoral muscles.
When Emily tasers and punches the black henchman, the tall one standing only a few feet away from him is looking around like he can't see her right in front of him.
The bomb that was meant to destroy a building exploded a few feet underwater and only caused a big splash, but didn't do any damage to Lydia's outfit or even chip her nail polish.
Emily has a chart of the Periodic System of Elements on the wall of her room in 1993. The chart shows the current names of heavier elements such as Nihonium (element 113) and Tennessine (117). These names were not assigned to these elements until 2016.
Lydia throws a bus showing the route number "88 Higgins" into an intersection where a Martin Luther King Jr. Drive street sign is visible. The 88 bus only runs through Chicago's northwest side; King Drive is on Chicago's south side. In the next scene, a news report shows that bus destroyed Buckingham Fountain, which is downtown and not near either the 88 bus route or King Drive.
The pills Emily took to make her invisible would not automatically also make the clothes and watch she wore become invisible with her.
In the liquor store scene when Lydia grabs Kenny to "kangaroo" him, as she jumps up through the ceiling, he disappears from her hands and she jumps alone, but then he reappears in the liquor store a few minutes later.