This anime does adapt the manga faithfully with some details being omitted where I assume is to save time to progress the story. It does sacrifice some character development and some world-building but it has little effect on the overall story. However, halfway through the 2nd season of the anime, it adapted a story from the novel adaptation of this series. This was not a bad thing since I did enjoy watching it but there were some minor inconsistencies here and there on character development and world-building. Although, these minor inconsistencies and adapting a story from another source does not obstruct the continuity of this series at all (as you will see in the last episode).
Overall, this is a good series to watch especially on the different style of the isekai genre where it is more of an uphill battle and there are actual stakes on the line if they fail to clear the quest (both short and long term). I also recommend to read the manga as well.
