Hi Phoenix,
thanks. I’ve found a solution.
In case anyone needs the same:
// All Entries with ‘//’ are visible within wp backend. all others are gone 🙂
// Portfolio
function mo_register_portfolio_type(){}
// Gallery
//function mo_register_gallery_type(){}
// Page Sections
//function mo_register_page_section_type(){}
// Showcase Slides
function mo_register_showcase_slide_type(){}
// Departments
function mo_register_department_post_type(){}
// Staff Profiles
function mo_register_staff_profile_post_type(){}
// Testimonials
//function mo_register_testimonials_post_type(){}
// Register Pricing
function mo_register_pricing_post_type(){}
// Courses
function mo_register_course_post_type(){}
// News
function mo_register_news_post_type(){}