The Hebrew that is translated into English as forms of “(to not) harden heart” is translated into other languages with their own vivid idioms; for example, Thai uses “black-hearted” (source: Bratcher / Hattoon, p. 272), Pökoot as makany kwoghïghitu mötöwekwo: “do not let become hard your heads” (source: Gerrit van Steenbergen), or Anuak as “make liver strong” (source: Loren Bliese).
The name that is transliterated as “Moses” in English is signed in Spanish Sign Language in accordance with the depiction of Moses in the famous statue by Michelangelo (see here). (Source: John Elwode in The Bible Translator 2008, p. 78ff.)
“Moses” in Spanish Sign Language (source)
Another depiction in Spanish Sign Language (source: Carlos Moreno Sastre):
The horns that are visible in Michelangelo’s statue are based on a passage in the Latin Vulgate translation (and many Catholic Bible translations that were translated through the 1950ies with that version as the source text). Jerome, the translator, had worked from a Hebrew text without the niqquds, the diacritical marks that signify the vowels in Hebrew and had interpreted the term קרו (k-r-n) in Exodus 34:29 as קֶ֫רֶן — keren “horned,” rather than קָרַו — karan “radiance” (describing the radiance of Moses’ head as he descends from Mount Sinai).
Even at the time of his translation, Jerome likely was not the only one making that decision as this recent article alludes to.