In the first attempt, I put the model directly into Cura and print with Generic PETG profile and printed it. It’s not clear at all, which is expected.
For the tests later, I switched to PrusaSlicer for a more advanced control of parameters.
Second attempt: Parameter to 2 infill to 0%
Third attempt: solid object with more normalized settings
Fourth attempt: enable ironing (failed)
Fifth attempt: disable ironing, adjust temperature, disable cooling
After five major tunings of the parameters, I had a printing profile that is very close to the result I found online. So I started to print test models five times to fine tune the speed and temperature.
It’s clear that there are bridging and overhang issues with the more transparent prints. I know that it’s because of the slow speed and lack of cooling.
Then I printed this project with the worst and best profiles. It’s fascinating that the appearance of PETG changes drastically with minor changes in the setting.