So I get that if I don't include localization for other languages, the text will show up as missing.

But there's essentially zero chance that I can transate everything into 10 different languages.
What's the standard practice here? Google Translate?

EDIT:
Ok, I'm seeing conflicting information:

From lilyophelia (LO Guide to Modding ES2):

- If you do not include localization files for a non-English language, then players using those language options will have missing keys; the game does not default to English values.

From the Starter Kit (ES2_Localization_Locales.xml):

Contains the new texts for the mod. If there is juste English language, it will be use for all localisations

So which is it?

Hey folks!

As you can see with this image, I am playing ES2 in french, and although the Example custom planets mod only has english text, the localization is properly displayed.

If you encounter situations where this doesn't work, please report it because it may be a specific case that's incorrectly handled by the game.