Based on your query, I would recommend Twee and Grammarly as they both offer features that can assist in teaching writing.
Twee is a versatile tool that can help you create content for your writing lessons. It allows you to generate dialogues, stories, and exercises related to your teaching topic. This can be particularly useful when teaching writing as it provides you with a variety of materials to use in your lessons. Additionally, Twee can generate vocabulary lists and design fill-in-the-gap exercises, which can be beneficial for improving your students' vocabulary and understanding of sentence structure.
On the other hand, Grammarly can serve as a personal proofreader for both you and your students. It checks for grammar, punctuation, and spelling mistakes, and offers stylistic and best-practice writing suggestions. This can help your students improve their writing skills and learn from their mistakes. Moreover, Grammarly includes a plagiarism checker, which can ensure the originality of your students' work.
In combination, these two tools can provide a comprehensive solution for teaching writing. You can use Twee to create engaging content for your lessons and Grammarly to help your students improve their writing skills and ensure the originality of their work.