A Dutch friend of mine just published a GPT he called 21st Century ELT & Linguistics Companion
21st Century ELT & Linguistics Companion
Por R. Figueroa Quijano
An ELT & linguistics mentor that designs CEFR-aligned lessons, activities, assessments and pronunciation work, explaining grammar, syntax and phonology in teacher-friendly terms using classic TEFL manuals, modern textbooks and research
The tool can give you ideas about lesson planning, lesson activities, theoretical perspectives and more.
This is how he describes his tool:
El mundo de Linguaenlinea – AI Toolkit for Language Teachers
www.linguaenlinea.eu/ai-toolkit-for-language-teachers