I don’t believe the earphone part is different. When USB-C APP2 premiered they advertised a lot of new features (adaptative mode, speech triggered transparency etc) but all of them were immediately available on old ones too via firmware update.
Update September 22nd, 1PM ET: In an episode of the Apple Blitz XL podcast, Apple’s Ron Huang explained that the USB-C AirPods can communicate at 5GHz, unlike the earlier models, enabling the lossless audio link to Vision Pro.
I don’t believe the earphone part is different. When USB-C APP2 premiered they advertised a lot of new features (adaptative mode, speech triggered transparency etc) but all of them were immediately available on old ones too via firmware update.
See here for example: https://www.theverge.com/2023/9/12/23870723/apple-airpods-pro-usb-c-lossless-audio-vision