No one has claimed to breed a BP morph into a BP/blood subspecies hybrid.
However, in the morelia genus (a genus in the family pythonidae, just like the genus python, and composing of snakes that are compatible with BPs for hybridiation), there have been visual morphs in hybrids. One of the popular ones is a jaguar morph carpet python crossed with a green tree python. The carpet/GTP hybrid is known as a carpondro, and the jaguar morph carpet/GTP hybrid is known as a jagpondro. Because of this, I believe it is possible for some, if not all BP morphs to be visual in hatchlings that are the products of morph BP x blood breedings.
I'm not a fan of hybrids. The only ones I've seen pics of is the Burmball, a Wall python (woma X ball). I recently saw a pic of another one but I don't remember what it was...