This requires just a little bit of command line knowledge, but overall it’s pretty straight-forward
- Open Terminal.app
- Change your path to the directory where the zip file exists
- type
zip -d Archive.zip __MACOSX/\*and hit enter (assuming your file is named Archive.zip)
The __MACOSX folder should now be removed from the zip archive.
Note: if the path or filename contains spaces, be sure to escape the space with a ‘\’. Example: archive\ name.zip