Have no idea what a proper name for the connector should be, I have one in the arrived package from CWWK store on Ali. Maybe Wikipedia has an article about connector types for fans (it has for storrage drive like SATA etc.).So, while I have probably found a fan that would fit inside the HUNSN, I ordered an adapter cable with a plug that is far too big. Does anybody know how these mini mini four pin connectors are called? (It's smaller than it looks).
Also, as this connector is mounted far too close to the edge of the board, ultra thin & flexible cables would be needed.
You probably need a L-shape connector judging by the picture you shared.