Maybe a bit "off-topic", but not quite so...
In the Slovene language Natrix tessellata is called "kobranka", while "kobra" is, of course, "cobra"...
https://sl.wikipedia.org/wiki/Kobranka
"Kobranka (znanstveno ime Natrix tessellata) po videzu, strupenosti in življenjskih navadah prav nič
ne spominja na kobro."
In the first sentence they make clear that N. tessellata has nothing to do with a cobra, either in aspect,
or in toxicity, or in its way of life. (There is also a "caveat" that scientific names and "popular" names
can be, and often are, quite apart.)
There is, however, no attempt to explain the "popular" name... Either it's just an invented "popular"
name, or... I don't know, maybe some of the Slovenes does?
BTW, the Croatian "popular" name is simply and plainly "ribarica", meaning "fisher" or "fisherman", only
in the female grammatical gender, that is "fisher-woman". I suppose, for the very simple reason that
"snake" ("zmija") in Croatian is of female (grammatical) gender, just as in e.g. German (DIE Schlange).