Kirschner is not slovenian - is a german name.
as people with german-orgin also were in Slovenia, Slovakia, Czech Rep. -areas also to find there.
also jewish people took often german words for lastnames.

orgin is at the profession "Kürschner" from old-high-german word kürsenaere = animal fur worker;
which is a loanword from old-russian "krzno" = fur -> middle-high-german "kürsen"

an interpretation to german word Kirsche = cherry is not correct ;)

slovenian svete = holy
to understand that they have taken sweet then because of pronouncing :)