How to retain metadata modification date when exporting modified videos from Photos app?

The reason there's problems with videos and the creation data is that videos do not have EXIF fields in them which contain the capture date. That's only for photos.

However, you can change the Title to include the ca[tire date and when exporting use the Tite as the new file name. This allows sorting by date by sorting by file name.

This AppleScript will do the job: Script: Batch Changing the Title to the Capture Date . Or this one to add additional info to the date: Batch Change Title to Capture Date-Description-Padded Sequential Numbers. The second script will give you this:

The scripts compiled as an applications can be downloaded from this tutorial site:  P01 - Applescripts from Photos’ User Tips Compiled as Applications  

Use 3rd party apps like GraphicConverter or exiftool to set the desired date to QuickTime:CreateDate tag (for years 1904-1970-) or Keys:CreationDate (for years 1-1904-. Apps like GooglePhotos might need their own tweaks for certain year ranges).

Photos.app 6.0 (macOS 11 Big Sur) grabs the date in the following order from mp4, m4v and mov movie metadata tags:

[Keys]          CreationDate                    : 2004:04:04 12:04:04+02:00
[UserData]      DateTimeOriginal                : 2003:03:03 12:03:03+02:00
[QuickTime]     CreateDate                      : 2002:02:02 12:02:02+02:00
[MacOS]         FileCreateDate                  : 2001:01:01 12:01:01+02:00

https://discussions.apple.com/docs/DOC-250002750

> as that for exiftool to have the correct creation date, I have to export the Unmodified video.. so I lose any mods I made to the video in the Photos app

You can "Export unmodified original" with "Export IPTC as XMP" and then combine the updated sidecar .xmp info to the original movie with a command like:

exiftool -m -P -overwrite_original_in_place -wm w -api QuickTimeUTC=1 -tagsFromFile movie.xmp '-QuickTime:CreateDate<XMP-photoshop:DateCreated' movie.mp4

I just tried it in Monterey Photos.app 7.0 and it works (Photos re-imports the movie with the updated date). If you have a folder full of movie and .xmp pairs, you can make a command that automatically does it for all of them and optionally update also location info and file dates to match the metadata date.

I have a command that does this all to .jpg and .xmp pairs but movies need adjustments to it. ...and macOS 11-12 Photos.app 6.0-7.0 have a bug that sets western and southern coordinates to the other side of the globe in the exported .xmp unless a modified command (or GraphicConverter) is used to bypass that flaw:

https://discussions.apple.com/thread/252258329

> as that for exiftool to have the correct creation date, I have to export the Unmodified video.. so I lose any mods I made to the video in the Photos app

Update: You can "Export unmodified original" with "Export IPTC as XMP" and then combine the updated sidecar .xmp files' info to the original movies with the command below.

exiftool -overwrite_original_in_place -api QuickTimeUTC=1 --ext xmp -tagsFromFile %d%f.xmp -api QuickTimeUTC=1 '-AllDates<XMP-photoshop:DateCreated' '-Track*Date<XMP-photoshop:DateCreated' '-Media*Date<XMP-photoshop:DateCreated' '-Keys:CreationDate<XMP-photoshop:DateCreated' '-Keys:GPSCoordinates<$XMP:GPSLatitude# $XMP:GPSLatitudeRef, $XMP:GPSLongitude# $XMP:GPSLongitudeRef' '-Keys:DisplayName<XMP-dc:Title' '-Keys:Description<XMP-dc:Description' '-Keys:Keywords<XMP-dc:Subject' '-FileCreateDate<XMP-photoshop:DateCreated' '-FileModifyDate<XMP-photoshop:DateCreated' .

It copies all updated .xmp sidecar Dates, GPS, Titles, Descriptions, and Keywords to the original .mp4, .m4v and .mov Keys and also sets the file dates so they are shown in QuickTime Player Title and Get Info and are re-imported to Photos.app.

https://exiftool.org/forum/index.php?topic=13167.msg71183#msg71183

p.s. that command bypasses Photos.app .xmp export error with GPS references. A year ago I sent feedback to Apple about this and now sent another.

macOS 11-12 Big Sur and Monterey Photos.app 6.0-7.0 ignore the standard for GPS data with its "Export IPTC as XMP" option.

According to the specification, the XMP GPSLatitude/Longitude tags have the reference directions included instead of in a separate tag in the form “DDD,MM,SSk” or “DDD,MM.mmk”.

https://exiftool.org/forum/index.php?topic=12634.msg68327#msg68327

https://exiftool.org/forum/index.php?topic=11969.msg64879#msg64879