First thanks for the good work, easyengine is a nice project.
Second, it’s too bad that WP CLI interface supports setting the locale/language in which wp should be installed but it seems like you forgot to implement it.
[--locale=] Select which language you want to download.
Could you add a flag to the create function to indicate which locale of WP to install ?
Meanwhile I’ll probably fork your code to hardcode the download of my locale but I guess I won’t be the only one asking for this feature.