Sorry for the long delay, but I just wanted to note that the lipo-version works for us. Strangely we had to disable the jit for the intel-build, if enabled starting erl results in
felix@fizfaz-air Resources % ./at_servr_release/erts-12.2.1/bin/erl
beam/jit/x86/beam_asm.cpp:168:pick_allocator(): Internal error: jit: Cannot allocate executable memory. Use the interpreter instead.
which works fine for the normal build. But this is maybe due to some security restriction in macOS 
, and is not a problem for us. We don’t need wxWidgets or other shared libraries, which made it simpler for us. Thanks for the help!