If you encounter the following when you reindex with magento, you probably did not install analysis-phonetic and analysis-icu plugins.
Error encounter
{"error":{"root_cause":[{"type":"illegal_argument_exception","reason":"Unknown filter type [phonetic] for [phonetic]"}],"type":"illegal_argument_exception","reason":"Unknown filter type [phonetic] for [phonetic]"},"status":400}
Resolution
Install the 2 plugins below. If you are using elasticsearch docker, docker bash to your docker and install from there
bin/elasticsearch-plugin install analysis-phonetic
bin/elasticsearch-plugin install analysis-icu