How can I adjust the sequential numbering scheme when exporting Photos?
Select the photos to export and then press: ⇧⌘E 

In the Export sheet, select the Photo Kind: and then select Sequential for File Name:, while leaving Sequential Prefix: blank, and Subfolder Format: to None.

Click the Export button.

Select a location for the photos to be exported to and click the Export button.

For the number of photos you mentioned, "~200", this will take a little while.

When the exporting is finished, then in Terminal change directory to the location of the exported photos.

cd /path/to/exported/photos


They will be named e.g. 1.png, 2.png, etc.

Use the following compound command to rename the files for a three digit zero padded filename.

for f in [0-9]*\.*; do mv -v -n "$f" "$(printf %03d "${f%.*}")"."${f##*.}"; done


The files will now be named e.g. 001.png, 002.png, etc.