There's a new project, Inshellisense[1], that provides fig's completion directly in the shell. Also check out zsh-autocomplete[2], and if you use iTerm2, the built-in autocomplete functionality[3].

[1]: https://news.ycombinator.com/item?id=38167363

[2]: https://github.com/marlonrichert/zsh-autocomplete

[3]: https://stackoverflow.com/a/53848666/