How to copy files to an SD Card without macOS metadata files?
These days most systems ought to be smart enough to simply ignore them if they don't know what they are.

macOS will put those 3 files [&amp; more in some circumstances] on every disk it ever sees, whether you want it to or not. There is, as far as I'm aware, no way to prevent this - all you can do is try to delete them right before ejecting the disk.

There's a bash script on Superuser - How do I keep Mac OS X from saving hidden files on my flash drive?
 which would appear to do this, though idk how many times you are going to have to authorise the sudo command; hopefully once per session not once per disk.

Personally, I invested in the paid alternative, BlueHarvest, which does the same thing in a 'set &amp; forget' manner &amp; is customisable for different drive types &amp; purposes.. 


  Built-in support for deleting: .DS_Store, ._AppleDouble, .apdisk, .AppleDouble (folders via smb), .com.apple.timemachine.donotpresent, .fseventsd, .Spotlight-V100, .TemporaryItems, .VolumeIcon.icns, $Recycle.bin, Desktop.ini, Icon?, Thumbs.db