MACBOOK air 2018 charger

Yes, you can use the 96W charger if you want. The laptop itself controls how much power is received from the charger. We always purchase the larger charger especially if we have different model Macs which ship with different sized chargers from the factory so that we know we have a spare charger which will work with any of the laptops. Keep in mind the 96W charger will be physically larger than the original charger.

You can use the 96 watt power adapter (and any larger adapters). The MacBook Air won't draw more power than it is designed to.