In French it’s Gauche and Droite so no problem here, but every product is labeled L&R because we live in a global market and English is clearly the dominating language. Most consumer product are made in China for the entire world so my guess is everybody understands L&R at this point.

Kaliwa, Kanan (left, right respectively)

Edit; this is in the Tagalog language, we use English for our gadgets

Indonesian does; kiri (left) and kanan (right). “Ki” and “Ka” are usually used in texts (e.g., for captions in newspaper/magazine articles), but for headphones, contact lenses, etc it’s normally just L/R.