Open seeeeew opened 4 weeks ago
Sorry to be the bearer of bad news, but the creator/maintainer of paimon.moe does not care one bit for anything aside from wish history. Furnishing sets have been abandoned for a long time. Achievements have buggy entries (go to https://paimon.moe/achievement and search for "Deianeira", for example). Community PRs to fix these things have been ignored for years.
There are alternatives to Achievements and Wish History (https://stardb.gg/, for instance), but AFAIK there are no other community projects that handle furnishings or furnishing sets. If you find or know of one, please share!
Xianyun doesn't have any favorite furnishing sets assigned. According to her wiki article, her favorites are Gathering of Gourmets and Qingce Cloud Residence, both of which already exist in the data and would only need to be assigned to her.