Factual error: When Cruella first drives her iconic car, being in Britain the driver's seat should be on the right side, not the left.
Suggested correction: Cars can be imported from overseas. It's very possible the car was imported from America.
Factual error: Dwayne Johnson is pursuing a thief. He gets into a Porsche Taycan and pushed the start button, and he can drive off. But you have to have the key fob in your pocket or bag. Porsche explains: "As long as your key is close when you grab the door handle, the system automatically checks the encrypted access code on the key. Once your code is validated, the door will unlock, and you'll be granted access to your vehicle." Dwayne had no fob, as the car was just parked.
Suggested correction: I assumed the car belonged to the guy who was stood just in front of it, so the fob would have been in his pocket, close enough to start it.
Maybe the owner was so stupid to leave the keys in the car. "Who can steal it, here in front of me?"
Maybe start it, but since he drove away, the fob would no longer be in his possession and although the car would continue running one time, it could not be restarted.
Factual error: Johnny's dad and gang come to over protection services to Moon and the singers. Despite almost no time having passed since the first Sing movie, as evidenced by Rosita's children having not aged, the gang appear to have been released from prison. The gang were in for armed robbery and at least one case of escaping prison. The minimum terms for those charges would keep them in prison for years.
Factual error: Rock Doves - even those used to people walking around in the city and on the sidewalks - would have flown away at the first sign of a predator, including a puppy - but they more or less ignored Clifford running toward them. (00:10:30)
Factual error: Tree foliage was unseasonal and inconsistent throughout the movie. For example, Autumn foliage (orange/yellow leaves) was shown, followed by a shot of a tree with Summer foliage (green leaves), then back to Fall leaves when Hildy was on her way to Thanksgiving dinner. At times, trees still had Summer foliage around Christmas time. By November in Massachusetts, trees would have few, if any, leaves on them (and they would not be green). (00:42:50 - 01:05:20)
Factual error: Morse code is supposedly being transmitted by the blinking street lights. They supposedly spell "For 3veryth5h1ng that 7iv3s is holy." I know Morse code. It was just a random scattering of letters. (01:00:05)
Factual error: During the escape from the farmers market a red London bus is in the background. Those busses aren't used in Gloucester.
Factual error: When the hackers take out Zagreb, Croatia, one shot shows the effect on a train in a subway station. Zagreb has no subway.
Factual error: The Black Watch sergeant major wears a crown over three chevrons, which was the correct rank badge for a company sergeant major until 1915. However, this is at least 1916 (as conscription has started and the men are wearing steel helmets, both introduced in 1916). CSMs had been redesignated as warrant officers in 1915 and now wore a crown on the lower sleeves instead.
Factual error: Unless left in the vehicle (not the case here), towed impounded vehicles do not have keys. Moreover, lacking keys, a valid registration, possibly proof of insurance, and new plates, vehicles bought at a NYPD auction are to be TOWED away. A newly-purchased auctioned vehicle, such as the Navigator in the movie, is "ticket-" or "citation-ready", not ready to be driven on the streets.