Multisite Support -> explain

[swissky]

Hey, could you please explain to me the Multisite setup a little bit more. How a Setup would look for a site like this, where we use MultilingualPress, so each subsite is a language:

example.com/en example.com/fr

The next question is about performance. I think the images need too much time to be visible. Sometimes just then when they are in the viewport. Yould you check if there is an "Preload critical images" supoort possible so leading images are not lazy loaded and then there is a Threshold for lazy loading images, so they are ready before they are visible?

Thank you