$ sudo port install mpich-default $ sudo port select --set mpi mpich-mp-fortran

Then try to build PETSc (minus the --download-mpich and CC, CXX, FC options).

That worked

You could also try to install most of the external packages:

$ sudo port install hypre ml parmetis metis hdf5-18 netcdf triangle \ superlu superlu_dist mumps

This instal seemed to work but how would I configure PETSc to use them?