Simplifying multiple nots:
const isVariant = e.match(VARIANT_TESTER);
const matchingFirstHanzi = isVariant?.[2];
const matchingSecondHanzi = isVariant?.[4];
// knotty read:
// const needToShow
// = !isVariant || (matchingFirstHanzi !== hanzi && matchingSecondHanzi !== hanzi);
// De-Morgan'd, easy to read:
// const needToHide = isVariant && (matchingFirstHanzi === hanzi || matchingSecondHanzi === hanzi);
const needToHide = isVariant && [matchingFirstHanzi, matchingSecondHanzi].includes(hanzi);
const needToShow = !needToHide;