Green (Japanese), Blue (USA/Europe), and Yellow (Rental) B-Boards all use the same connector and are cross-compatible with each other's A-Board.
Orange (South American) and Gray (Asian) have unique connectors and must have a matching A-Board and B-Board.
There is nothing in the software or electrically that prevents these boards from working together, it's just the Orange and Gray boards have differently gendered connectors.