Add "Read More" under Blog Excerpt

Add this code to the Custom CSS field on the Settings tab of your Blog widget’s settings:

[class*="card-content__CardContentTitle"]+div:after {
    content: "Read More";
    font-size: 12px;
    display: block;
    position: relative;
    top: 30px;
    text-decoration: underline;
    transition: all 0.3s ease;
}
[class*="card-content__CardContentTitle"]+div:hover:after {
    transform: translateX(10px);
    transition: all 0.3s ease;
}
[class*="card-content__CardContentTitle"]+div {
    overflow: visible;
}

Result: