add_rewrite_rules prefix everything

I need to setup a WP rewrite structure in which I prefix all urls with a custom (dynamic) prefix.

So the urls would look like this:

www.example.com/myprefix1/

www.example.com/myprefix2/

www.example.com/myprefix1/a-page

www.example.com/myprefix1/a-category

www.example.com/myprefix1/a-cpt

www.example.com/myprefix2/a-cpt

etc.

So far I came up with this:

  $options = implode( array('myprefix1','myprefix2', '|' ); // my prefix options

// add a rule for each registered post type (??)
        foreach($postTypes as $postType){
                    $new_rules['(' . $options . ')/(.+?)/?$'] =  'index.php?post_type=".$postType."&' . self::$sitePrefixName . '='. $wp_rewrite->preg_index(1).'&pagename=". $wp_rewrite->preg_index(2);
                }

// add a rule for the home page (?)
                $new_rules["(' . $options . ')/?$'] = 'index.php?' . self::$sitePrefixName . '='. $wp_rewrite->preg_index(1);


        $wp_rewrite->rules = $new_rules + $wp_rewrite->rules;

It works, but I believe e.g. taxonomies are not included here. I’m trying to make this as flexible as possible so that future CPT’s, tax etc. will work as well.

Am I doing the right thing here or are there other ways to do this?

Thanx!

Have you ever consider to use rewrire_rules_array filter to alter $rewrite_rules?

 /**
 * Example of Changing All Rewrite Rules
 *
 * @param  array $rewrite_rules The compiled array of rewrite rules.
 * @return array                The compiled array of rewrite rules (altered).
 */
function wpse_263624_rewrite_rules_example( $rewrite_rules ) {

    $prefixes = array( 'otro', 'esto' );
    $prefix_regexp = '(' . implode( '|', $prefixes ) . ')/';
    $new_rewrite_rules = array();

    $match_pattern = '/\$matches\[(\d)\]/si';

    foreach ( $rewrite_rules as $rewrite_rule => $match ) {

        // Incrementing $match becaouse prefixes goes as capturing group.
        $new_match = preg_replace_callback( $match_pattern , function( $m ){
            return sprintf('$matches[%d]', $m[1] + 1);
        }, $match);

        // Adding Prefix Group and New Value for our match.
        $new_rewrite_rules[ $prefix_regexp . $rewrite_rule ] = $new_match;
    }
    return $new_rewrite_rules;
}
add_filter( 'rewrite_rules_array', 'wpse_263624_rewrite_rules_example' );

It ends up in something like this..