Isn’t really a blueprint question,but selectors can only show things that are known.
That could be any from the list in the docs including text/roll your own. I do not think the field accepts a template or will do a list or a loop to build the YAML either. I think the only way is manually build a list. I have long lists of languages in my All-TTS script blueprint manually maintained, for instance.
There is the possibility something could be done with an object selector where some other template can build and update the YAML file to read from.