bp_core_validate_blog_signup( string $blog_url, string $blog_title )

function bp_core_validate_blog_signup( $blog_url, $blog_title ) {
	if ( ! is_multisite() || ! function_exists( 'wpmu_validate_blog_signup' ) ) {
		return false;
	}

	/**
	 * Filters the validated blog url and title provided at signup.
	 *
	 * @since BuddyPress 1.2.2
	 *
	 * @param array $value Array with the new site data and error messages.
	 */
	return apply_filters( 'bp_core_validate_blog_signup', wpmu_validate_blog_signup( $blog_url, $blog_title ) );
}