How to change the position of video icon on the product picture

Hello,

Please try adding the following Custom CSS in the Global Custom CSS area under Theme Settings >> Custom CSS.

body .product-additional-galleries {
    left: 0;
    top: 0;
    bottom: 0;
    right: 0;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    pointer-events: none;
}

body .product-additional-galleries > div {
	pointer-events: auto;
}

body .product-video-button {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
}

Regards.
Xtemos Studios