We are looking for the same feature. We have many Brands with multiple locations and atm is impossible to add them to the platform. This makes it so much harder to manage them and does not allow us to fully migrate to Hubspot, having to work on two separate CRMs - hence not opting for the paid version yet. Also the hierarchy of the Companies (Parent-->Child) is a bit confusing on the platform. I would have expected it to look more like:
We also had this challenge, we wanted to see the full visual of all the child companies, grand child companies, great child companies and how they are connected on very BIG accounts.
We created an internal tool back in 2017. Today it's open to all HubSpot customers, if you want to try it out then drop me a message and we will make it happen 😊.
Short video below showing how it works inside of HubSpot with a 2 way sync: