Well, identifying where Konosuba Season 3 is in the novels can be tricky. It depends on various factors like the story progression and the author's narrative choices. Sometimes, elements from multiple parts of the novels could contribute to the season's plot.
The end of Konosuba Season 2 in the light novel shows the characters growing in their own ways. Megumin becomes more proficient in her explosion magic, albeit still with her comical over - the - top love for it. Darkness continues to be... well, Darkness, with her strange masochistic tendencies. And Kazuma is still trying to make the best (or worst, depending on how you look at it) of his situation in this strange world.
The story progresses with more comical and adventurous elements. Kazuma's schemes to get rich quick or gain some sort of advantage usually backfire in hilarious ways. The party also meets new allies and foes. New areas of the fantasy world are explored, bringing with them new types of quests and challenges.
I'm not entirely sure, but it's very likely. TvTropes is a comprehensive database for all kinds of fictional works. Given Konosuba's popularity, especially in the anime and light novel world, it would make sense for there to be a section about its visual novel on TvTropes. You could check by searching for 'Konosuba visual novel' on the TvTropes website.