https://exiftool.org/exiftool_pod.html
exiftool -a -b -W %d%f_%t%-c.%s -preview:all <directory containing DNGs>
exiftool -a -b -W %d%f_%t%-c.%s -preview:all <DNG filepath>
exiftool -a -b -W %d%f_%t%-c.%s -xmp <DNG filepath>
https://exiftool.org/exiftool_pod.html
exiftool -a -b -W %d%f_%t%-c.%s -preview:all <directory containing DNGs>
exiftool -a -b -W %d%f_%t%-c.%s -preview:all <DNG filepath>
exiftool -a -b -W %d%f_%t%-c.%s -xmp <DNG filepath>