One of the upcoming Asus ROG Phone 6 models, ASUS_AI2201_B, has been certified by TENAA. This confirmed some of the key specs, though we’re not sure if this is the vanilla phone or the Pro. Given the memory configuration, it is probably the Pro model.
The phone measures 172.8 x 77.3 x 10.4mm, basically the same dimensions as the ROG Phone 5/5 Pro. Only a White colorway is listed, but unfortunately there are not photos attached yet. Despite remaining the same size, the new mode has managed to shave some weight and is now down to 229g (all 5-series models weighed 238g).