You can actually get away with quite a lot in terms of mismatching platforms. We target an embedded system (Xilinx Zynq). We cross compile the Erlang+Elixir system into the Linux platform build. Then for the application code we just build the release using no_erts. We're building that application on X86, just making sure that the Erlang/OTP/Elixir versions match and it works.

We have some ports that are separately cross-compiled and provided on the target.