Problem is that i downloaded 3tb of games this way lolYou can't without converting them and it's a pain in the ass. Save yourself a headache and just google "Wii U USB Helper reddit workaround" download whatever games you want from there, throw them on an sd card inside "install" folder, and install them to an external hard drive or internal with WupInstallerGX2.
What you need to do if you insist on using your WUD images is use wud2app by Fix94 here: https://github.com/FIX94/wud2app and then install the output using WUPInstallerProblem is that i downloaded 3tb of games this way lol