This is interesting. People use Discourse in so many different ways!
@alltiagocom can you explain your use case in some more detail? Why do you want to create a topic that contains an automatically generated list of topics with a certain tag? Can you share an example of what you’d like this to look like?
I think I understand @sbrawley case, for organically creating a FAQ. But unless you’re talking about a huge list, why not just maintain a topic with a list of links in it manually? That way you can also control the appearance of it and specify the ordering. Your members seem to be on the right track, though a topic (which you can make a wiki and maintai n collaboratively) is of course more suitable than a word doc.
There is Discourse Doc Categories which lets you specify a topic as index for documentation, where you can insert links that are then used in the sidebar navigation.
You can see an example of this in action in Documentation. Example index: Using Discourse Index