Apple has seeded watchOS 7.4 RC to developers ahead of its public release. The build number is 18T195.
watchOS 7.4 includes new features, improvements, and bug fixes, including: • Ability to unlock your iPhone X and later with Apple Watch when you attempt to use Face ID while wearing a face mask • Option to classify Bluetooth device type in Settings for correct identification of headphones for audio notifications • Ability to stream audio and video content from Apple Fitness+ workouts to AirPlay 2-enabled TVs and devices • Support for the ECG app on Apple Watch Series 4 or later in Australia and Vietnam • Support for irregular heart rhythm notifications in Australia and Vietnam