The images that you upload in the editor are stored in a separate folder from the regular media library image folder from WordPress. The reason is that Brizy creates different image sizes from the same image to be used in certain cases (like when you users will access your website from mobiles or tablets).
WordPress creates these thumbs or different image sizes as well, but because Brizy does it differently (we think better) we needed to store them in a separate folder on the server.
Note that what you see in your Media Library are all the images from your WordPress install that can be from multiple folders from your server. More over, what you actually see in your media library in the WordPress admin, are the original images you've uploaded, but if you login on the server you'll find different versions of those images on different sizes.
What actually happens
When you add an image on your page via Brizy, we automatically create 6 sizes of that image: 2 for desktop view, 2 for tablet view and 2 for mobile view. One for each normal and retina displays.
When a user will access that page, the image that is most suited to his device will be loaded, thus optimising the experience and load speed on the page.
If you are testing page speeds using tools like GTMetrix you might see images on your Brizy pages as non-cache. Give it a bit of time, the images will cache but it is a process that needs to take place first. The images used in Brizy are provided in dynamic mode first, but once you reload the link, a request will be sent to the server, the images will be cropped and uploaded in the static mode and as as final step they will be cached.
Don't do this
Don't upload optimized images in the WordPress Media Library, because Brizy will take them from there and create the different sizes I've mentioned above and those images will need to be optimised again.
Don't use any image optimisation plugins because they don't access the image folder Brizy is storing the images in so they will not work.
Do this instead
Upload your images and create your pages/website using Brizy. Don't think about the optimisation process until you are done. Once that happens use our native ShorPixel integration to optimise all your images at once at the end. ShortPixel is one of the most popular and highly regarded image optimisation platform in the industry.
Here is a step by step tutorial on how to optimise all your Brizy images.