- Share the individual files or,
- Share the sub-folders or,
- Make exact copies, move them all into one sharing folder and share that
There’s no easy solution. This is a file management problem and not something that can be solved by encryption. Large companies use corporate intranets to simplify sharing and then apply the encryption to the underlying files. Smaller organisations or individuals are stuck with sharing individual files unless you’re willing to build an intranet/extranet to handle or this.
Personally I’d go with the last option. Have a group-share folder and then share that with set and subsets of authorized persons.