Hasselblad and Rolleiflex are very different cameras, yet very similar. Whereas Rolleiflex with its fixed lens is compact but fairly limited, Hasselblad is a modular system that can grow with you. But they both take stunning 6x6cm pictures on 120 size film.
I’ve shot hundreds of rolls with both cameras. This video compares these two and talks about their strength and weakness. Yes, very subjective but based on a fairly solid experience :-)
See also:
For Hasselblad: https://youtu.be/4q5ugi2mosY
For Rolleiflex: https://youtu.be/iVUA-h6le7w