Do you have the WaniKani Open FrameWork and Item Info Injector scripts installed as well?
IIRC I was very confused about why Anime Sentences wasn’t working when I was gathering scripts myself. First, I realized I forgot to install Open FrameWork, and then I looked in the replies of the Anime Sentences script post and saw a comment saying Item Info Injector was now needed because Anime Sentences’ own was outdated (or something like that). I’m not particularly technologically literate tho lol 