Hi,
Most of the 100+ games published with the Dialogue System use the built-in editor. It has the best integration with Dialogue System features, such as being able to drag assets into the Sequence field, set up scene-based UnityEvents in the inspector, etc., that external editors can't do.
Some external editors that are popular to use with the Dialogue System are articy:draft (paid), Chat Mapper (paid), and Twine (free). Yarn is a lot like Twine. There isn't a Yarn importer, but there's a Twine importer. Ink is also popular, but it works differently from the Dialogue System, so it's a little more challenging to set up the integration. The list of importers is on the
Import & Export page. There is also a JLC Converter download on the
Extras page. This is the tool that Mografi used to write their dialogue for Jenny LeClue - Detectivu.