Set calibre cover style on per-library basis

In calibre I have some different libraries in which I store different kinds of books. Most of them don’t have a "built-in" cover, so I use the cover generation function of calibre to create a cover depending on the library, e.g. :

• library 1: water, blocks, title size 100px, …
• library 2: water, ornamental, title size 200px, …
• library 3: silver, ornamental, title style italic, …

but I need to manually rebuild the style each time I switch the library. I’d like to set for each library a single cover style (colors, style, font, size and so on) that I can easily apply by just clicking on Edit metadata > Generate cover.

Is that possible? If so, how can I do that?