Order Query loop with Post Meta by ASC / DSC

Hi there,

Can you try this snippet?

add_filter( 'generateblocks_query_data', function( $query_data, $query_type, $attributes ) {
    if ( 'post_meta' !== $query_type ) {
        return $query_data;
    }
    $classes = preg_split( '/\s+/', $attributes['className'] ?? '' );
    if ( ! in_array( 'relationship_sort', $classes, true ) ) {
        return $query_data;
    }
    if ( empty( $query_data['data'] ) || ! is_array( $query_data['data'] ) ) {
        return $query_data;
    }
    $get_post_id = function( $item ) {
        if ( is_numeric( $item ) ) {
            return absint( $item );
        }
        if ( is_object( $item ) ) {
            return absint( $item->ID ?? $item->id ?? 0 );
        }
        if ( is_array( $item ) ) {
            return absint( $item['ID'] ?? $item['id'] ?? 0 );
        }
        return 0;
    };
    usort( $query_data['data'], function( $a, $b ) use ( $get_post_id ) {
        $a_id = $get_post_id( $a );
        $b_id = $get_post_id( $b );
        $a_time = $a_id ? get_post_time( 'U', true, $a_id ) : 0;
        $b_time = $b_id ? get_post_time( 'U', true, $b_id ) : 0;
        // Latest first. Swap $b_time and $a_time for oldest first.
        return $b_time <=> $a_time;
    } );
    return $query_data;
}, 11, 3 );

Then on the Post Meta Query block, add the relationship_sort class under Advanced > Additional CSS Classes.

Let us know how it goes.