Revealing mistake: When Wolf Jackson touches a headstone as he and the police are about to raid the church, you can see the headstone wobble when his hand lightly touches it, revealing it to be made of a soft, perhaps Styrofoam-like material and not a real headstone.
Continuity mistake: When Deep Dark Secret breaks the jar to free the emotions, look at where the emotions are standing, and how the huge piece of glass lands behind them. In about three seconds, the piece of glass changes position, and some of the emotions switch places. (00:33:08)
Continuity mistake: When Deadpool is talking to Wolverine's skeleton, in one shot the skeleton's mouth is closed, but in the next shot it is open.
Continuity mistake: When Anita Caprioli and Pasquale Petrolo are talking by her car, the car door hits Lillo. The two awkwardly chat for a while; during the conversation, their hands change position a few times between shots. (00:51:30)
Factual error: Andy crashes on an uncharted planet, and his personal assistant says the atmosphere is 2% oxygen. This is over 90% less than the oxygen concentration on Earth. When Andy comes across his crashed and burning ship (the "Borealis"), the fire is burning just as brightly as it does on Earth. The fire should be shown as burning much lower due to the small amount of oxygen.
Continuity mistake: When the possessor moves the tricycle down the street to the Ghostbusters HQs, the doors get blown off the entrance, and the Ghostbusters log/sign falls to the ground (seemed like a soft landing, in that it didn't seem to shatter... but when the long shot of the ice/frost proceeding to the firehouse (Ghostbusters HQ) is shown, the fallen signage is nowhere to be seen. (01:29:38 - 01:32:11)
Other mistake: In the first scene, they skid around a corner; there are many other skid marks on the same corner. I imagine the drivers had to repeat the recording several times.
Continuity mistake: At the gas station, Thelma and Ben are talking to random people Thelma thinks she knows. Meanwhile, her family is on the way there. The sun is going down in this sequence and it's noticeably getting darker. Before they run behind the building, it's suddenly lighter outside and gets darker again.
Other mistake: When Abbott is talking to Axel for the first time, he is flipping through a book that has files and pictures on Axel. One of them is a picture from when he got arrested after he got thrown out of the window. It is made to look like it was a picture taken of him at the time of his arrest, but it is a direct screen grab from Beverly Hills Cop.
Character mistake: When Jodie and Colt are in her trailer, discussing what should be done next, Jodie suggests Colt needs to cross the border. But they are in Australia, which only borders the sea.
Visible crew/equipment: When the 6 main characters open the hatch to the sewer, there appears to be a crew member helping them open it. There is only 6 of them in the scene. But, there is a seventh person at the top who looks to be wearing a m95 mask. This is also in the opening scene of the first trailer.
Continuity mistake: After the bad biker bites Noel, he removes the rearview mirror from the windshield and smacks the bad biker with it. However, when Noel tells Katie to drive the car, in the exterior shots as she sideswipes another car, the rearview mirror is back up on the windshield; then it's off again. (00:33:35)
Continuity mistake: In the staff room of the toy store, Callum gives Jack his Monopoly box to hold. The box does a 180° spin between shots, twice.
Continuity mistake: When the milkman is drinking milk in the bar and talking to the Tony the Tiger actor, the amount of milk in his glass changes with the different camera angles. It goes from 2/3 full to mostly full to half full back to mostly full. (00:54:56 - 00:55:45)
Continuity mistake: When Jack has his temperature taken near the start of the film, the thermometer in his mouth goes from right-side up to upside down, then back to right-side up between cuts.