This obviously is not peak mushoku. It's a side story that is still very essential. It covers the life of Sylphy since the mana disruption and her connection with Princess Ariel and Luke. This episode might be a bit boring and season 2's first few episodes will heavily focus on Rudeus' journey and he will eventually meet Sylphy so this episode is really important in giving context about Sylphy.
Story-wise its really good 8/10
Animation/art style -> While this isn't what mushoku often looks like and is a downgrade, I think this episode was outsourced so for the actual s2 the animation should be much better. This doesn't mean the episode was appalling by any means, just means that It was not on par with s1. 6/10