Quick one, after re-installing my Notebook, I had to configure lot of things again and I wasn't happy with my earlier Python venv setup.
I was taking a deeper look into pipx and I think that's way easier to use. It just take care about a venv per package that I'm going to install, I don't have to take care about anything on my own.
I tried it and after learning about the inject feature, mentioned by cs01 in a GitHub Issue (Archive: [1], [2]) it was no problem to install Pelican including some Plugins via pipx:
pipx install pelican pipx inject pelican pelican-pdf pipx inject pelican markdown pipx inject pelican pelican-read-more