Hi there. Author of said inventory plugin.
If you ever wish to migrate you should be able to retain most of what you did on XOA side (I'm thinking tags), but you'll have something that's more standard and require less setup as long as the XOA API is accessible to the machine running the playbook.
You can keep the groups with the composable groups in your inventory plugin configuration:
simple_config_file: plugin: community.general.xen_orchestra api_host: 192.168.1.255 user: xo password: xo_pwd validate_certs: true use_ssl: true groups: kube-master: "name_label == 'kube-master'" compose: ansible_port: 2222