Comment by polonbike

Not completely what you are looking for, but still open source plans of house: Wikihouse https://www.wikihouse.cc/

Earthships are also said to be open source, but the plans are (definitely) not free https://earthshipbiotecture.com/

You can also check Open Source Home, by Studiolada (those are free, but the plans are in french) https://www.countryliving.com/remodeling-renovation/news/g46...

Open Source Ecology is now listing a house in their list of builds https://www.opensourceecology.org/extreme-build-of-the-seed-...

Open Building Institute is also promoting a configurable house https://www.openbuildinginstitute.org/