I18N Subsites: Use translation for default site not for subsite

I'm exploring methods to translate the template of my site and I was able to make a subdir that has the translation with help of gettext and your plugin. However I want to use the language as the main language for the website and not in a subdirectory. `example.com/` instead of `example.com/es/`

When I set default_lang to `es` it doesn't show the translations on the main domain. 