my pitch to avoid transphobic language is, as always, to avoid euphemism.
"(coercive) assigned sex at birth" is not a euphemism, it is an accurate description of a literal process that includes a social, legal, and all too frequently medical component. it is legal assignment into a sex class. it describes something done to us. it is something done to every single person who has any official birth documentation.
when you use it as a euphemism to imply any specific trait (e.g. "AMAB" to imply "has a clitoris/penis capable of penetration" or "AFAB" to imply "has a uterus capable of gestation") this is a transphobic assertion. it is equating the particulars of the body with one's assignment, which is functionally how cissexism works. the point is to obscure the legal/economic reality of assignment into a class through suggestion that it is merely descriptive of bodies.
assignment does not describe bodies. it is used to determine what forms of medical abuse someone is subject to, what medical care and bodily modifications a person can legally pursue and economically access, with what required documentation and formal surveillance. in this way, it can describe what traits one is punished for having, what legal restrictions to bodily autonomy one must navigate around, but it does not describe what traits one has.
if you find yourself searching for a term to euphemistically suggest a sexed trait (whether a genital configuration, a gestational capacity, a hormone ratio, an amount of breast tissue, etc.) without having to say it outright, whatever you reach for will likely end up reifying sexgender (which is the construct that creates intersex and transgender/transsexual subjectivities). there is no non-transphobic way to use euphemism to avoid talking about the particulars.
and you can tell people use these terms euphemistically, because they will complain at terminology like "TMA"/"TME" by stating that it "describes genitals" or is "demanding to know one's birth sex." To say someone is transmisogyny affected (structurally, legally, socially, economically) is a relationship to a particular mode of oppression. Same with saying someone is transmisogyny exempt. It describes a relationship to structural power. It literally does not suggest anything about one's physical traits at all.
now, because of how transmisogyny operates materially, it is a result of the sex assignment process, and the enforcement of that assignment. so trying to define TMA without respect to CASAB essentially attempts to redefine transmisogyny away from its material analysis of how it operates. however, TME has no direct relationship to CASAB-- perisex cis men, perisex cis women, intersex cis men, intersex cis women, perisex trans men, intersex trans men, some perisex nonbinary people, some intersex nonbinary people, etc. are all TME. it's a relationship to a particular power structure, not a physical descriptor.
if you want to avoid transphobia, then make a practice of thinking through what you're actually talking about (a practice? documentation? physical traits? a relationship to power? someone's gender?) and then talk about it with specificity.
and if you discover that talking about it specifically would be inappropriate (e.g. you wanted to ask if someone "is AFAB" but your actual question is "do you have a penis?" and you don't want to ask them that because you're in a context where you aren't in a sexual encounter and this information is not necessary) then do not say it. using a euphemism would not make that question any less inappropriate, it would just layer transphobia on transphobia.
