Wikipedia’s list of English prefixes categorize trans- and cis- differently.
Trans- is “native”. That is, it comes to us through Medieval French and has been fully integrated (linguists would call it productive) into modern English.
Cis- in “neo-Classical.” Meaning, it was lifted from Classical Latin into the modern age thanks to science, and now forms words like cislunar and cisgender.
So, based on this incredibly complicated, complex analysis I decree that being transgender is more natural and native to anglophones than being cisgender is. Amen.