Placing a Collection page in a SUBdirectory

You can place collections inside of static folders, so use cases like;
/en/blog/some-cool-article work.

If you’re trying to create a semantic solution where the URL path represents CMS item categorizations, etc.;
/recipes/dinner/halloumi-avo-salad
/califonia/sacramento/102-my-house
then no that’s not supported in Webflow.

You can create a visual effect for this using various JS hacks, but if your goal is SEO those redirects are not good practice for canonicals.

The only way around this is a reverse-proxy to manage your paths, correct your links, and to rewrite your sitemap.xml. A decent bit of programming work to get that automated correctly.