Huawei 40W Wireless Fast charger can charge 27W wireless fast charger. First of all, the technology of wireless fast charge is based on electromagnetic induction technology. When there is a wireless charging protocol between the charger and the phone, the charger can provide wireless charging for the phone through electromagnetic induction technology.
The output power of Huawei 40W wireless fast charge is 40W, while the output power of 27W wireless fast charge is 27W. Due to the existence of the wireless charging protocol, when Huawei 40W wireless fast charge and 27W wireless fast charge match, the charger can provide enough energy to charge the phone.
It should be noted that there may be differences in charging protocols between different brands and different models of chargers, so it is necessary to confirm whether the charging protocol between the charger and the mobile phone matches when using. If the charging protocol between the charger and the phone does not match, it may lead to slow charging or no charging problems.
To sum up, Huawei 40W wireless fast charger can charge 27W wireless fast charger, but you need to confirm whether the charging protocol between the charger and the phone matches.
It can be charged, but the charging speed will be slower.