Register multiple styles / scripts in register_block_type

Not supported yet, see the corresponding Github Issue.
I found a workaround in order to at least register additional block styles:

register_block_style(
    'create-block/myblock', array(
        'name'         => 'style2',
        'label'        => 'Style 2',
        'style_handle' => 'create-block-myblock-style-2',
    )
);