К элементам, заданным как встроенные и фоновые стили не применяются
Можно только прямо в div svg вставить и тогда стилями менять.
<!DOCTYPE html>
<html>
<head>
<title></title>
<style>
div {
width:24px;
height:28px;
}
div>svg {
fill : #fff;
background-color:#8875f0;
}
div:hover>svg {
fill : #8875f0;
background-color:#fff;
}
</style>
</head>
<body>
<div><svg width="24" height="24" viewBox="-2 -2 27 24" version="1.1" xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false">\
<path d="M12.892 13.745s.427.038.656-.247l.448-.563c.216-.28.738-.458 1.249-.174.676.382 1.55.982 2.149 1.541.33.278.407.688.182 1.121l-.002.009c-.232.408-.541.791-.932 1.148l-.009.006c-.44.367-.946.58-1.487.404l-.01-.014c-.972-.275-3.304-1.464-4.79-2.649-2.431-1.918-4.159-5.082-4.637-6.778l-.015-.01c-.176-.543.039-1.049.404-1.488l.007-.008c.357-.391.739-.701 1.148-.932l.009-.002c.432-.225.842-.149 1.121.182.367.379 1.056 1.291 1.54 2.149.284.51.106 1.033-.173 1.248l-.564.448c-.284.23-.247.657-.247.657s.834 3.156 3.953 3.952zm4.907-2.616c-.167 0-.303-.135-.304-.302-.014-1.83-.564-3.288-1.634-4.332-1.072-1.045-2.427-1.581-4.027-1.592-.168-.001-.303-.138-.301-.306.001-.167.136-.301.303-.301h.002c1.762.012 3.258.606 4.447 1.764 1.19 1.162 1.802 2.765 1.817 4.763.001.167-.133.304-.301.306h-.002zm-1.595-.624h-.007c-.168-.004-.301-.143-.297-.31.024-1.038-.273-1.878-.906-2.569-.63-.689-1.495-1.065-2.645-1.149-.167-.013-.293-.158-.281-.325.013-.167.158-.293.325-.281 1.294.095 2.32.548 3.049 1.345.733.8 1.092 1.807 1.065 2.992-.004.165-.139.297-.303.297zm-1.558-.522c-.161 0-.295-.126-.303-.289-.051-1.03-.537-1.534-1.527-1.588-.168-.009-.296-.152-.287-.319.009-.168.151-.296.319-.287 1.308.07 2.034.819 2.101 2.164.009.167-.12.31-.288.318l-.015.001zm6.817 3.469c-.605 4.877-4.172 5.185-4.83 5.396-.28.09-2.882.737-6.152.524 0 0-2.438 2.94-3.199 3.705-.119.119-.258.167-.352.145-.131-.032-.167-.188-.165-.414l.02-4.016v-.001c-4.762-1.323-4.485-6.295-4.431-8.898.054-2.603.543-4.736 1.996-6.17 2.61-2.364 7.987-2.011 7.987-2.011 4.541.02 6.717 1.387 7.222 1.845 1.675 1.434 2.528 4.867 1.904 9.895zm-.652-11.113c-.597-.548-3.007-2.298-8.375-2.322 0 0-6.33-.382-9.416 2.45-1.718 1.718-2.322 4.231-2.386 7.348-.063 3.118-.146 8.958 5.484 10.542l.006.002-.004 2.416s-.035.979.609 1.179c.779.241 1.236-.502 1.981-1.304.408-.44.971-1.086 1.397-1.58 3.851.322 6.812-.417 7.149-.526.777-.253 5.177-.816 5.893-6.657.738-6.022-.358-9.83-2.338-11.548z"/>\
</svg></div>
</body>
</html>