It seems to me that the SOC simply says that the second therapist should evaluate and confirm the first therapist's diagnosis.
The requirement that the second therapist should be a psychiatrist if the first therapist is only at a master's level
does not rule out them both being psychiatrists.
Neither of the letters are inherently limited in scope, they should work internationally.
I would insist upon having them in English, though.
It seems to me that generally somebody sees a therapist specializing in GID to have most of their therapy.
After they have received their first SRS recommendation letter, they visit a psychiatrist.
The psychiatrist's job is to be more of just a "sanity check" on the diagnosis and the patient.
The
Standards of Care covers this on page 8.