You’re right - huge projects require a lot of organization up front and when done in Hype, it pays to look at all the ways you can make things modular and re-use components.
We basically built Module 1 and worked out all the bugs, then duplicated it to build the other five. When the Spanish translations were ready, we duplicated the final English version and switched out text and audio where needed. The project took about 4 months with a team of 3 people plus a few contractors here and there. It had its challenges but was well worth it in the end!
If I can be of any help on your project when you know more, let me know. You can message me privately via my profile.