I’ve just created a shortcode out of a hook to be able to insert it wherever I want.
The question is: how can I make a second one?
If I replicate this snippet, the function does not work as the function has been already declared.
there are three parts to that shortcode that need to be unique – that is the shortcode_name, the the_callback_function_name of which you will see it twice in the code, and the custom_shortcode_hook label.
As a note: that function is a bit of a hack, and i would only recommend using it in extreme circumstances. Not advisable to have lots of different ones as the extra db queries it will generate can soon mount up.