Wii Flow 4.2.1 is designed to be dynamic and animated, next to USB Loader GX a widely used USB Loader.
Wii Flow has In-build support for loading backed up games from an SD card. Wii Flow is a well designed alternative to USB Loader GX
Download Wii Flow 4.2.1 2019 updated below:
Wii Flow 4.2.1 2019.zip[mirror]
Disclaimer: Wii Flow USB loader is also used to load pirated copies of Wii games, but this practice is illegal and not the intention of the software.