
Factual error: At the end when Skeksis enters the crystal chamber, in the overhead shot you can see 22 arcane symbols around the crystal when there should only be 18, one for each exiled skeksis. (00:45:53)

The Hoodlum - S4-E1
Factual error: Diamond's car phone, quite a rarity in the 1950s, attracts a lot of attention. But the car should have a huge antenna attached to make the gadget work (it doesn't), and Diamond would not be getting direct calls - they'd have to go through a mobile operator first.

Factual error: Jessica receives a call from a prisoner at a State Institution. It shows up on her cell phone as "Unknown." All calls from prisoners are collect calls, and the receiver is asked if they will accept the charges. (00:41:20)

Factual error: Captain Carrillo is target shooting with a hand weapon. She empties the magazine, but she catches the magazine and hands it to her ranger partner instead of letting the empty magazine fall to the ground. As a trained military officer and training with special operators, catching an empty magazine is an extremely bad habit and practice, which is a big no-no. (00:40:23)

Factual error: There are two Marines posted at Marine 1, the Presidential helicopter. Their pants are ridiculously long and not the image of Marines with well-fitted uniforms. Their position of attention is wrong, with the hands clenched and placed on their thighs as opposed to being fixed at the sides. Worse, when they saluted with their right hands were above the service cap brim, instead of the fingertips touching the bottom of the brim.

Funny Money - S1-E10
Factual error: The characters travel to Cyprus where they are seen driving on the right hand side of the road, when in Cyprus they drive on the left.

Factual error: Every episode in the first half of this series begins with the same phrase and the same map of the Italian peninsula. Said map though misspells, in a very Japanese way, the north-eastern city of Trento, wrongly appearing as Torento. (00:00:01)

Factual error: Although he is openly an SD officer, Huth does not wear the SD insignia on his cuff.

Stage West - S1-E6
Factual error: In the background, in the scene when Simmons is talking to the stage driver, you can see cars driving by on a road in the background. (00:12:06)

Factual error: Kai checks out his phone repeatedly and the date indicated is "Wed, Aug 22." Just a scene after, Jenny is shown with an August 2019 calendar in the background. August 22 2019 was a Thursday, not a Wednesday. (00:06:00)

What If... Captain Carter Were the First Avenger? - S1-E1
Factual error: When Stark starts telling about the Tesseract, the colonel shows surprise that Nazis were in Norway. Peggy answers with "Close. HYDRA." The scene is set in 1943, and Norway had been occupied by Nazi Germany for three years already. Them being in Tønsberg should not come as a great surprise to an Allied commander. (00:07:10)
Suggested correction: I feel like this falls under the "Not a mistake because it's an alternate universe" umbrella. We're in an entirely different universe with a different timeline in this episode.
The show also makes a point that the only difference should be the minor choices or events befalling the MCU characters, and how these minor things have huge consequences for them, basically creating a new alternate timeline. Basic world history before these events is not affected by the new timeline.
Basic, unaltered world history does not apply with this because we are talking about an alternate WWII from the beginning. One with Schmitt/Red Skull as propaganda minister of Hitler, Hydra superseding the SS, super soldier serum, Stark tech, the Tesseract, etc. It is not WWII as we know it, even without the "what if."

Factual error: Luka's military officer cap isn't a Russian cap, it is a Hungarian police cap. The Russian cap is bigger.

Factual error: Early in the episode Stonebridge removes a bullet with the casing still attached from Scott's leg. (00:11:00)

Making Dead Things Look Nice - S4-E7
Factual error: When Carolyn leaves the hotel and gets into the taxi, you can briefly spot the license plate. In Austria, the first part has only one or two letters; here it is three letters. For Salzburg, it should be S or SL.

Wax Doll Castle Murder Case: File 3 - S1-E9
Factual error: The culprit merely drops a chandelier from the ceiling in an unplanned move. From that simple action, the whole building - a huge castle - catches fire so quickly you'd think it's made out of papier-mâche soaked in gasoline, not stone.

The Origin of the Silver Surfer: Part 3 - S1-E3
Factual error: When Silver Surfer is battling Galactus just outside the Earth's orbit, Surfer is depleted of his Power Cosmic and looks to draw energy from the sun to replenish it. The sun is pretty close to the Earth's orbit, when in reality it is 93 million miles away.

Factual error: The series takes place during the 1930s prohibition era. The $50 bill projected on screen is series 1953A with signatures of Ivy Baker Priest and Robert Anderson.

A Ghost for Scotland Yard - S2-E8
Factual error: Bearing in mind the episode takes place in London, Sir Arthur MacCready is driving his Rolls Royce. The car has the steering wheel on the left hand side. A true British Rolls Royce would have the steering wheel on the right side. This is a Hollywood Rolls Royce.

Michelangelo's Birthday - S3-E31
Factual error: The very beginning of the episode shows Michelangelo's Birthday circled on the calendar, and it is shown as the second Tuesday of the month as well as being the 13th day. The second Tuesday of a month can never be the 13th. The earliest the 13th of a month can be is the second Thursday.
Suggested correction: This is simply wrong. If a month starts on a Thursday, the first Tuesday will be the 6th, and the second will be the 13th.

Factual error: Detective Superintendent Hamilton has red fabric within the crowns on her rank insignia. This would be correct for most British police forces, but the Metropolitan Police uses blue fabric instead.