Oh that’s great, I was just about to say that I’ll take some time and see if the platform-ststm32 code can be hacked to quickly support this board.
What is your final platformio.ini and the modifications you had to do to the Python script(s)?
This would also be very intersting to submit as PR to GitHub - platformio/platform-ststm32: ST STM32: development platform for PlatformIO to support the board (one ‘board’ for the M7 part, one for the M4 part)