ExpressionUniversalizer is a newish script from Lloyd Alvarez at AE Scripts that will “convert the expressions in your projects so that they are compatible with After Effects running in any language.” ExpressionUniversalizer goes a step beyond an older script by Charles Bordenave (nabscripts) that's also at AE Scripts, TranslateExpressions, which translates expression control names according to the language of the running version.

AE template author Felt Tips has 2 tutorials about how to use ExpressionUniversalize, including details about writing directly in a universal expression language if the script is not able to universalize some expressions. There's also an expression preset that can help. Here's the main tutorial:

All About Universal Expressions (And Expression Universalizer) from Felt Tips on Vimeo.