Golden Kamuy, Fumetsu no Anata e Recommendations
Both are very unique mangas. They both have action (guns, swords, although there are greater, and more supernatural powers in Fumetsu no Anata e), explore different environments through adventure (the mc is always on the run/running into danger), and have a goal/mission that drives the narrative. They give off similar feelings of action and adventure, as well as satisfaction.
There is also romance in both, although it is more one sided in Fumetsu no Anata e.