For ESFJ, the dominant is Fe, supported by Si.
ISFJs are often described as dependable, considerate, patient, practical, and service-minded. That comes out in their writing with closed circle letters, indicating quietness. Curved garland connectors indicate kindness. The sample we reviewed in our meeting showed a healthy baseline with a slight bounce in the letters.
There was also a tendency to use the right-hand side of the margin, indicating future orientation. The desire to serve can be seen in the sweeping ending of the e's - as if a hand was reaching out to help. Wavy lines indicate humor.
ESFJs are often described as consistent, sympathetic, outgoing, harmonious, and tactful. For the ESFJ samples in the room, both had wide left margins and a well-organized page. Both also showed extensions on their letters and loops in their d's and t's stems. These loops can indicate a need for approval and positive feedback.
I've also noticed those loops in my writing, and as ENFJ I share the dominant extraverted Feeling function.