The Ubiquiti POE-54V-80W-EU is a PoE injector that delivers 54 V DC with up to 80 W power and is specially designed for Ubiquiti devices such as EdgePoint models. The UniFi U7 Pro Outdoor Access Point is powered with PoE+ (802.3at) at 54 V, which is compatible with this injector. The UniFiSwitch Flex Outdoor also supports PoE/PoE++ and is therefore compatible with PoE injectors that supply 54 V.

You can therefore use the POE-54V-80W-EU to power the UniFi U7 Pro Outdoor and the UniFiSwitch Flex Outdoor, as both devices support PoE with 54 V and the injector provides the necessary power.