Galaxy A9 (2018) Qi Wireless Charging:

Galaxy A9 (2018) Wireless Charging

Qi Wireless Charging not supported,
but Accessories available.

Unfortunately, your Galaxy A9 (2018) doesn’t have Qi Wireless Charging integrated. However, you can use a Wireless Charging Adapter for your device in order to make it Qi compatible or view the list of all Qi enabled Phones.