Filter or plugin that replaces special characters?

Question

My agency believes that special characters are a bad thing (since there were compatibility problems between Mac and Windows in the (ancient) past). So rather than submitting pictures with keywords, titles and so on with "Einstürzende Neubauten" I have to submit "Einstuerzende Neubauten". I do not want to ruin my database but rather have a postprocessing script or plugin that replaces "ü" by "ue", for example. Is there something like this? Some call to exiftool?

Edit: I forgot to mention that I am using Lightroom. So there may be plugins that have such functionality already. Metadata Wrangler is quite good, but I cannot figure out a way to replace patterns with it.

Answer 1

Exiftool could do this with the -api "Filter=" option, but the command line could get long and messy.

Using your example, the command would be something like this:
exiftool -api "Filter=s/ü/ue/g" -TagsFromFile @ -all:all DIR

The only trouble would be that the individual substitutions would get long and you would have to deal upper and lower case separately.

Additionally, if you're on Windows, you may have to add the -L option to deal with the accented characters.

---

Edit: Alternate version if you have Perl installed.

With Perl installed and the main Exiftool Perl code installed (not the executable), then Unicode::Normalize can be called and this simpler command can be used.
perl exiftool.pl -api "filter=use Unicode::Normalize; $_= NFKD( $_ ); $_=~ s/\p{NonspacingMark}//g;" -TagsFromFile @ -all:all DIR

Based upon this StackOverflow answer.

The only problem is that it would convert ü to just u.