I had been using this guide, for when to install mods. https://docs.google.com/spreadsheets/d/1vislrHkbvsqlN0m5jtDxDcSzlnA5D6ABSZy5TG1O8FQ/edit#gid=1194891517
Also, I wasn't aware that EET end had to be installed for to complete the merge.
All I know was, that it was heavly recommended to install all mods before EET End.
Therefore, I went on to take a look on the game to check, if anything was correctly installed.
Now, before I spoke with Lauriel on G3's discord server, I made the mistake of deinstalling everything for a fresh install.
So, thank you so far for all the immediate responses.