thank you Thomas!
I finally got it working!
info.xml is actually not the issue. it looks kind of double when having an own section - NC is using the first one and oC the second one. As they can co-exist (just tested), its fine from an app-dev point of view
within Personal.php you need two functions returning the same. again double - but ok.
public function getSection() **NC**
public function getSectionID() **oC**
If an app only uses one of the existing categories - you are done here.
But it gets interesting when using an own section
within PersonalSection.php, there are 2 basic differences.
class PersonalSection implements ISection **oC extended with getIconName()**
class PersonalSection implements IIconSection **NC extendet with getIcon()**
So this would be the time to introduce two different PersonalSettings.php
Or do you have a suggestion to evaluate if the one or the other class is available?