The sharpest cases are the systems whose foundational vocabulary was coined in English by English speakers rather than carried into English from somewhere older. Where a Sanskrit, Hebrew, Greek or Latin term reaches a modern reader through a translator's choice, an English-coined term reaches the reader as its author left it, and an argument about what it means is an argument about English usage rather than about a rendering.
Much of nineteenth and twentieth century Western esotericism sits in that second class. The Golden Dawn's grade names and ritual scripts, the working vocabulary of modern ceremonial magic, the terms of Wicca and of the wider Pagan revival, and the language of a great many twentieth century new religious movements were all written first in English by writers whose own language it was.
The contrast is easiest to see where one system exists in two languages at different removes. Guido von List's Armanen runic system was composed in German in 1906 and 1908, and everything an English reader knows of it arrives through a translator. Its later English-language reception, the commentary and elaboration written about it by English speakers, is a separate body of material composed in English about a German original.
Naming which of the two a statement is about is not a technicality. It decides whether a disputed term is List's or his translator's, and on more than one occasion the two have not agreed.