Plugins para cambiar imagen al pasar el mouse en WordPress

<style>
img {
    opacity: 0.8;
    filter: alpha(opacity=40); /* For IE8 and earlier */
}

img:hover {
    opacity: 1.0;
    filter: alpha(opacity=100); /* For IE8 and earlier */
}
</style>

.img-contenedor img {
-webkit-transition:all .9s ease; /* Safari y Chrome */
-moz-transition:all .9s ease; /* Firefox */
-o-transition:all .9s ease; /* IE 9 */
-ms-transition:all .9s ease; /* Opera */
}
.img-contenedor:hover img {
-webkit-transform:scale(1.25);
-moz-transform:scale(1.25);
-ms-transform:scale(1.25);
-o-transform:scale(1.25);
transform:scale(1.25);
}
.img-contenedor{overflow:hidden;}

.img-contenedor img {
filter: url('#sepia'); /* Versión SVG para IE10, Chrome 17, FF3.5, Safari 5.2 and Opera 11.6 */
-webkit-filter: sepia(0%);
-moz-filter: sepia(0%);
-ms-filter: sepia(0%);
-o-filter: sepia(0%);
filter: sepia(0%); /* Para cuando es estándar funcione en todos */
filter: Gray(); /* IE4-8 and 9 */

-webkit-transition: all 2s ease;
-moz-transition: all 2s ease;
-ms-transition: all 2s ease;
-o-transition: all 2s ease;
transition: all 2s ease;
}
.img-contenedor img:hover { 
-webkit-filter: sepia(100%);
-moz-filter: sepia(100%);
-ms-filter: sepia(100%);
-o-filter: sepia(100%);
filter: none;

-webkit-transition: all 2s ease;
-moz-transition: all 2s ease;
-ms-transition: all 2s ease;
-o-transition: all 2s ease;
transition: all 2s ease;
}