This is the hearthling that works best by being out of town, loaded up with some fine crafted goods/wares/etc to go out and trade with other towns (off-map content in single player). Could help trigger event/campaign chains and attract lucrative caravans to your town, upgrade the rudimentary trade posts in your own town to attract high tier resource caravans, and go on excursions (go off-map) as mentioned above.
Could provide access to exclusive gameplay resources (i.e. not just events or campaigns but actual stuff you make) like new crops, recipes that have high nutrition/bonus effects, or even new items for military use, or even new materials to build with or crafter recipes. But you can only get those resources/recipes through trading for it - you can’t make them yourself.
Going into higher tier, it might be specialized per race and create its own special resource (like gold, but unique to its race) that you can use to trigger town-boosting effects or unlock higher tier game content. e.g. Rayyan Caravaneer (boosts caravan event rewards), Ascendancy Envoy (boosts new hearthlings starting attributes), and Dwarven Foreman (boosts chance of crafter classes crafting rare variety items as opposed to fine items only) - as examples of possible unique abilities