Looking for generic meta-language translation and serialization processor

I've got a software interface that I intend on supporting various protocol standards each with different serializations. I'm looking a for a and ASCII based translation language and stylesheet system similar to XSLT, but one that would handle:

1. Translation of serializations (XML, JSON, Protocol Buffers, etc, etc)


2. Translation of grammars


3. Data dictionary translations


4. Translate Unit conversions for numbers

Any ideas on a translation and/or stylesheet language that can do this and store its schema in a ASCII format? Does it have good software support? (hopefully open-source)