ACF get json by name.

functions.php

<?php
/**
 * Returns the ACF JSON filename by group name.
 *
 * @param string $field_group_name Name of the ACF field group
 * @return string|bool
 */
function get_acf_json_by_name( string $field_group_name ) {

	$field_group_lookup = [
		'hero' => 'group_59e226a200966.json',
		'cta'  => 'group_59e226a200967.json',
		// Add more field_group_name => file_name pairs here.
	];

	if ( ! isset( $field_group_lookup[ $field_group_name ] ) ) {
		return false;
	}

	return $field_group_lookup[ $field_group_name ];
}