Hello,

Unfortunately, there is no option in Theme Settings available to increase the size of brand images in the sidebar on the shop page.

You need to add the following Custom CSS in the Global CSS Area under Theme Settings >> Custom CSS.

.woodmart-woocommerce-layered-nav .swatches-normal.swatches-brands .filter-swatch > span {
width: 80px !important;
height: 60px !important;
}

And for the circular containers please provide with admin panel login details of the website to check it myself and help you out accordingly.

Best Regards.