According to a report from Android Police, one of their readers purchased a 10W Anker wireless charger which they assumed would allow it to charge the Pixel 3 at 10W. However that was not the case and it was discovered that it only charged at 5W. When Anker was contacted regarding this issue, the company claimed that Google had put the limitations in place.
“Also, what we learned is that Google’s official wireless charger can provide 10W for the newly-released Pixel 3 and Pixel XL 3, however, according to our quality engineer, Pixel sets a limitation for a third-party charging accessories and we are afraid that even our fast wireless charger can only provide 5W for these 2x devices.”
Google has since confirmed that this is true, claiming that this is due to a “secure handshake” being required that apparently only the Pixel Stand can provide. We’re not sure if Google will remove these limitations in the future, but it does seem to a be a bit unfair for those who might prefer third-party wireless chargers, or who might have already bought one and don’t see the need to buy the Pixel Stand.