No, an authentic Apple Watch Ultra lacks a hidden cameras.

YouTubers are being tricked by counterfeiters with fake Apple Watch Ultras that have cameras in the crown.
If you see a viral video that claims the Apple Watch Ultra is equipped with a hidden camera, you are actually watching a reminder of how some unethical companies and sites will do anything to fool the gullible. Recently, videos claiming the Apple Watch Ultra had a hidden camera have appeared on social media websites, especially TikTok. Apple knock-offs are not new, but the manufacturers try to replicate the hardware as closely as possible. Google Play Store icons are a sure sign that you have purchased a fake Apple Watch. This is because the watch runs Android. The digital crown also has a camera. The lack of watchOS is a reliable indication that the watch is not a genuine Apple product. If the “Apple Watch Ultra”, which is being sold at a significant discount from the retail price, is being sold new, this is another sign that it’s not genuine. Apple Watches that are genuine run watchOS and will not have cameras after September 1, 2024. This is evident from the many teardown videos of actual Apple Watch Ultras. Many Chinese sites that advertise the fake Apple Watch Ultra list Android v8.1 – from 2017 – as the operating system. This is why the Google Play Store icon is prominent. Some videos claim that resellers on Amazon sold them fake Apple Watch Ultras. Others ordered from popular Chinese online shopping sites such as AliExpress. The safest way to buy an Apple Watch Ultra, or any other Apple products, is from Apple’s official website or from a well-known Apple authorized reseller. It’s better to buy an Apple Watch Ultra directly from Amazon — an authorized Apple reseller, rather than through a reseller hosted by Amazon.