As far as I know Gleam is the only strongly typed language on BEAM, which is important to me since I don't like dynamically typed languages.
But of course Elixir gets optional types now.
Purerl - Erlang backend for PureScript, a few folks are using this in production - https://github.com/purerl/purerl
Caramel - Ocaml for Beam, seems dead - https://github.com/leostera/caramel
and more probably dead projects at https://github.com/llaisdy/beam_languages