GrantMTG

It looks like STM32H5 is a mainstream equivalent of the low power STM32U5 line. I have not had time to study it yet, but the H5 may have the same...

There are now "classic" libraries from STM for the U5 and H5. I'm no competent enough to do the libusb_stm32 work, but perhaps this will help someone who can: https://github.com/STMicroelectronics/stm32u5-classic-coremw-apps...