As widgets are outside post content, i couldn’t find the way to parse blocks inserted inside widget area for ex. "sidebar-1"
We use something like below for parsing post contents,
$post = get_post('100');
parse_blocks($post->post_content)
But for widgets, i couldn’t do it like below,
ob_start();
dynamic_sidebar('sidebar-1');
$widget_content = ob_get_clean();
parse_blocks($widget_content)