Technically there is no such thing as a “dwarf lionhead”. A lionhead rabbit is a lionhead rabbit. They are a small breed, which typically does not exceed 3.75 lbs in size. They do have dwarfism mixed into their gene pool since the breed was reportedly created by crossing a Swiss fox with a Nethie. Other small breeds were also mixed in along the way as the breed was developed. So, I suppose in this case, the word dwarf is being used as advertisement. But lionheads don’t get very big anyway.
Holland lops are a dwarf breed. They carry the dwarfism gene and they aren’t supposed to exceed 4 lbs.
Now there is the scenario where your bunny may not have inherited the dwarfism gene. What does that mean? He will be larger than what is considered acceptable according to the standards set for both breeds. Lack of the dwarfism gene doesn’t mean he will be big though. Those are still two small breeds so even without the dwarfism gene, I doubt he would exceed 5 lbs. Hopefully that helps.