I don't think Lacerte Form 1041 allows the input of a foreign address for the fiduciary.

Check out Section 7701 and particularly Regs Section 301.7701-7.  If the foreign trustee is the only trustee, the trust would likely fail the tests under §7701 and be classified as a foreign trust, which has tax consequences as well as reporting requirements that would otherwise not be applicable to domestic trusts.