Correct, found all of those, they are all not what I am looking for (unless I am blind).
The part I am after looks very much like the barometric pressure sensor GY-68 from the project you linked as well as the VERTER buck-boost there. So much so that I was thinking of re-using those to create the part myself (but it’s still a major effort for me to do it right). It does not look like the Adafruit or the SparkFun modules.
Potentially, the part may also be called SHT21 (see the page I linked in the original post), and I now even found a page showing a Fritzing layout with those modules: https://alxhou.wordpress.com/2012/07/01/multiple-sht21-softi2c/. But as you can see, the part is not drawn according to Fritzing quality, and I cannot download it anyway (could contact the guy of course if I cannot find the solution otherwise).
Does it make sense?