I'm working on a web-based Indesign file translation system: https://indesign-translator.com/ It extracts all text, translate them (manually or with google translate, up to the user), and re-download with styles and layouts kept.

I started it as I was making a booklet about meteorology for kids in Lao language. I tried an automatic transation tool and was amazed to see it was keeping the format, so I dived into the markup file for Indesign, called IDML. InDesign is such a great software.