Change all words in a list of filenames that are ALL CAPS To Capitalized

I want to do this without resorting to changing the list of filenames to all lowercase which messes with a bunch of intentionally ALL CAPPED acronyms.

For example I would want words like TPB, GN, HC, OGN, DC, OS, UK, USA, DCPAE, MacGuffins etc and many many more to not be effected by an "all lower case" method.

(I assume I could use a group to specify these words but I don't know how exactly to tell AR not to change "these" words with the "all lower case" new case method) but words not specified in the protected group could be "all lower cased" and then "Capitalized" using 2 new case methods.

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