I received the Huawei Wireless Charger along with the Watch GT as part of the Mate 20 Pro pre-order promo.
Wireless charging is fast (15w) but I also noticed that it's powered by the 40w charger and cable that comes as standard with the phone. That means you can use it to supercharge the Mate 20 Pro if you're in a rush.
It's great having the option of convenience (wireless) or speed (cable). Also means I have a spare charger, which I can leave at work (or whenever).
I remember when using iPhones I always had a charger at home, in my bag, and at work - as I knew I'd get caught short at some point each day.
Of course, it's likely I'll never need to use my spare charger with the Mate 20 Pro, as the battery lasts all day (and then some), but it's great to have the option.