Several blocks in one folder / plugin

$ npx @wordpress/create-block@latest blocks --template @wordpress/create-block-interactive-template
$ cd blocks/src/
$ mkdir "blockname"
$ mv * in "blockname" 

Duplicate the “whatever blockname” in the src folder to add new blocks.

In functions.php:

foreach ( glob( get_stylesheet_directory() . '/blocks/build/*' ) as $block_directory ) {
		register_block_type( $block_directory );
}