I don’t recommend Zephyr, especially if you use Jira Cloude, not Jira standalone server. It’s slow, with many limitation and it does not have so many usefully features as new products/plugins have. Zephyr for Jira Cloude has even more limitations. Furthermore, it’s perhaps most expensive test management plugin for Jira. Take a look at Xray, it looks very nice. I haven’t use it in practice, but there is a public demo and you can try it yourself for free. Xray has many good features and in my opinion it can be a very nice tool.
I’ve forgotten to mention: it’s cheaper than Zephyr