Google is likely to be making a wearOS model of the Fitbit Charge.
9to5Google noticed this FCC entry for the Goertek-made SZGG8BL6, which strains up with different Google units. Like the Fitbit Charge, it has Bluetooth and GNSS, however lacks Wi-Fi, whereas its e-label suggests it has a display screen and will run wearOS just like a mysterious wearable noticed in Google adverts.