I think the default structure of what Hatch does is ideal:
hashed_root = sha256(str(project_root).encode('utf-8')).digest()
checksum = urlsafe_b64encode(hashed_root).decode('utf-8')[:8]
virtual_env_path = data_directory / normalized_project_name / checksum / venv_name
The data directory in this standardized approach would be platformdirs.user_data_dir('.python', appauthor=False) / 'env'.
Note that it is necessary to incorporate the path to the project because the same name might be used elsewhere, perhaps for testing. IDEs like VSCode have that information necessarily so they would be able to resolve the path to the virtual environment.