I am trying to enable some features for Subscriber user role in a eCommerce theme where originally had be set for Admin role and I like to modify that. I tried AAM plugin but for this specific site it does not show those features so I can place a check or un-check them. I know AAM or any alike plugin serve as an interface and there are ways to look through the files/codes to make this happen. I found in wp-includes/capabilities.php is where this gets managed but I am assuming not for each specif site as I can't find anything about other sites in there. Does each site have its own capabilities.php somewhere?
I believe you'd need to modify user roles on each site individually (if I'm understanding your question correctly).
There's a great plugin I use frequently called WPFront User Role Editor that allows you to check/uncheck user capabilities like you mentioned. The free version should be fine for what you're trying to do. I personally use the paid version just because I like to have the extra options when I need them, but 90% of the time the free one works fine.