Thanks for your question. Thanks as well for adding the details of what you’re trying to accomplish; very helpful.
You can find quite a log of information about MLA’s CSV support in this earlier topic and the topics it links to:
Announcing the MLA CSV Data Source Example plugin
The example plugin is in the current MLA version so you can ignore the instructions about the Development Version. Here is another topic with a minor update:
download url
However, you don’t need to go to the trouble of export-edit-import for your immediate task. You can use MLA’s IPTC/EXIF mapping rule support for tasks such as replacing hyphens with spaces or other routine text-editing chores. Here are two earlier topics that will give you a better understanding of what’s possible:
Bulk replace a word in media titles
Combine image ISO, Shutter speed, Aperture with decription
I hope that gives you what you need to complete your work. I am marking this topic resolved, but please update it if you have problems or further questions regarding the above suggestions or the earlier topics. Thanks for your interest in the plugin.