Using ISO date format (YYYY-MM-DD HH:MM:SS)

Hello, I was wondering if there is a way to tag the earliest date associated with an MP4 video in the Title field...
What I want to do is essentially, renaming MP4 files based on the following criteria...
So I'm guessing the easiest way is to tag the TITLE field using Format Value with the format string as follows...

%_directory% - RETRIEVED %_file_create_datetime% - %_filename%

Then, convert the title tag to filename...

Unfortunately in doing this, it currently comes out in the weird American date format!

- RETRIEVED MM/DD/YYYY HH:MM:SS - .mp4

I'm using MP3Tag for MacOS so it's using Wine.

Any tips would be appreciated!
Thank you for an otherwise fantastic application.

That does not look easy esp. as you have all the data already there. You can rename the file directy with the format string that you use to modify TITLE.

To reformat the %_file_create_datetime% you can use a regular expression:
$regexp(%_file_create_datetime%,'(\d\d)/(\d\d)/(\d\d\d\d) (.*)',$3-$1-$2T$4)
Please not that not all characters are valid for filenames, e.g. the colon isn't and probably the slash isn't for a MAC.
Use that regular expression instead of the plain field name.