Change file names

This is not a feature of my plugin as yet, but I may add it in the future. If you need it urgently please leave a comment on this page

https://lhero.org/portfolio/lh-image-renamer/

I’ll then have your email then so we can discuss a suitable donation to the project to make it happen, otherwise my day job must take priority. Forum rules prevent us discussing such matters here

Otherwise you could use this plugin to do it:

https://en-au.wordpress.org/plugins/rename-media-files/

It is a really good plugin, it will rwname existing files, but it is a one by one approach and that may not be what you are after.