In the last eight years I have used Mathematica quite a lot for doing Natural Language Processing and text mining.
Here are couple of links that describe such activities:
[1] “Statistical thesaurus from NPR podcasts” :
[2] “Natural language processing with functional parsers”
Both blog posts have links to Mathematica packages and guides for doing NLP.
The approaches in those links are more-or-less language agnostic. I have used them to make search engines that combine (i) English, Spanish, and French, and (ii) English and Malay.
You might find this discussion interesting, “Convergence of synonym networks” : Convergence of synonym networks .
As for your question:
“Let’s say I’d want to separate the syllables of Spanish… would that be doable here?”
I have not used separate syllables of Spanish, only appropriate stemmers.