Development tools for Zephyr on STM32Workbench for Zephyr: VS Code extension to set up, build, flash and debug Zephyr applications on STM32.Devicetree manager: browse, edit and visualize Zephyr devicetree, STM32CubeMX-like for Zephyr.
sorry for the late reply. The good new is that ST has released a new version of STM32CubeMX - v 4.7.0 - that supports SystemWorkbench 😀
It is a good starting point.