I can't find any because I don't know what TERFs call themselves (the term appears to be solely used by their detractors). Maybe my google-fu is lacking, but it seems to be hard to find. When I google things like "transgender and gender existentialism" I get only (unsatisfying) rebuttals and some poorly-thought-out complaints about trans people.

I think my s.o.'s viewpoint is a little more nuanced than "trans women aren't real women"