That would be the way to go for sage9 indeed (as @carlosfaria explains). In sage 10 I got it working by adding “add_theme_support( ‘woocommerce’ );” to sage/app.php -> in after_setup_theme action.
That way you won’t have Blade support but you can edit Woocommerce templates by creating a woocommerce folder under resources folder. Copy paste templates from Woocommerce there and edit them to your likings.