Greasy Fork is available in English.
您最好的pixiv小说下载助手，支持下载单页、系列、作者、标签、收藏夹的小说
I'm currently working on improving the bulk download feature for user collections. It's proving to be more complex than I initially anticipated, and I've tried several approaches that haven't quite worked out yet. The idea is to have options to download individual novels as separate TXT files, or to package multiple novels into a single ZIP archive. The regular user features are still planned and coming, but they'll take a bit more time.
Single and serie novels are downloadable, but batch download for users page does not work (https://www.pixiv.net/en/users/[ID]/novels).
Hope this can be fixed soon. Thanks.