Multisite using subdirectory structure and Google

I’m considering multisite for a new project that will be similar to a franchise site, where individual sites will be structured as city specific subdirectories, like: domain.com/city1, domain.com/city2, etc, each with unique local phone numbers.

Does anyone know if Google assigns a trust or authority score to each individual sites —- or are all pages and posts treated as if they are all housed under a single site because of the subdirectory structure?

I’m also wondering (in terms of SEO best practices) what extent I can use generic community/shared posts and pages that will be used by and linked to from all sites within the network (such as service pages, legal pages, etc)? Or should each site have dedicated pages even though the content is the same on each?