Hi @ruem11,
It is probably possible but may be complicated, you need a knowledge and understanding the structure of theTouchGFX I think. I also tried to find a guide in the past but with no luck.
If you still want to spend a time for it, I think better is visit the ST’s forum about TouchGFX also TouchGFX documentation and find how to start.
However the LVGL seems be more achievable. Although they do not have a gui editor and objects must be created via coding but have easy to use simulator in the Visual Studio.
Also in their documentation you can found a Porting section, which will help you. I also made a simple porting guide for Mbed but I am not sure how much up to date it is at the moment.
BR, Jan