Best practices to work on files between Teams

Hi,

I am working on the migration of my on-premises data to SharePoint online.

My teams are set up, each team corresponds to a M365 group: HR, Accounting, Management, Employment Service, etc.
Each employee will be part of one or more teams. Each team has a document library, and only team members will have access to the document library.

The question is as follows: what is the best practice for working on files betwwen Teams?
Example: the HR team has a folder in its document library named Recruitment. The assistant managers are not part of the HR team but need access to a subfolder of this Recruitment folder.

I see 3 options:

1. i break the inheritance in the document library and set specific rights for the assistant managers.
2. I share the subfolder using a direct link, SharePoint sharing function.
3. I create a second document library for the human resources team where all the files that will be shared with the other teams will be located

For options 1 and 2, the "business logic" for the HR team is respected, meaning that all files in the Recruitment folder are located in the same place. However, I have no visibility on shared folders. At a minimum, we can play with folder colors to quickly identify shared folders, but at the scale of the organization, this seems risky to me.
For option 3, the visibility of shared folders with the other Teams is quick and easy, but the files in the Recruitment folder are then found in 2 document libraries, which is not intuitive for the HR team.

Could you please tell me what the good practices are? Are there any other options?