On B-Greek, Greek is our bread and butter, and Hebrew, Latin, and linguistic gobbledygook are also relatively common. But participants have widely differing ability to read any of these languages (including obscure jargon).
Be merciful. If you are writing about a topic that mere mortals can grasp, write something mere mortals can read. You are very welcome to write in Greek, Hebrew, Latin, or gobbledygook, but if you do so, provide a translation. Διὸ ὁ λαλῶν γλώσσῃ προσευχέσθω ἵνα διερμηνεύῃ (therefore the one who speaks in a tongue must pray that he may interpret).