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.
For me I had to import the project WITHOUT selecting the "Copy projects into workspace" option, and I also had the workspace and the generated project shared the same root directory.