Dou,
I am not following that guide. Besides that is for project output files.
I am creating a msix package to MS Store. The app is for a .NET Maui Windows Platform app.
After I select Project->Publish->Create App Packages... appears, then the attached image. There is no option to select and Output folder.
Try it with a .NET Maui app that you want to submit to the Store. Where can you change the Output folder for the created App Packages?