Using solvers that are obtained by other means (such as homebrew)

[algebravic]

Using solvers that are obtained by other means (such as homebrew)

[marcogario]

As long as the python bindings for the solver can be found by the python interpreter that is running pysmt, then you should be able to use solvers installed by other means.
However, newer versions might have changed their interface, so it is not a given that the python interface would work.
If the problem you are trying to solve can be represented in SMT-LIB, you can always use that interface with any solver (even ones we do not support via the python bindings). See an example in https://github.com/pysmt/pysmt/blob/master/examples/generic_smtlib.py