You can surely cross any two strains with one another, but you're not going to get the same plant from every seed (as is when you purchase a bag of WW seeds). That type of targeted breeding takes time and alot of genetic knowledge of the plants and specific strains that you're working with.
If you do cross, then you're going to be randomizing all of the different genetic traits from the two parents within each seed.
Now, I've also only seen breeding first hand a couple of times, so someone may come in here with more experience and tell you other than what I mention above. Either way, with determination and patience you should be able to identify all of the traits that you enjoy and breed for them in future seed batches.
Start a grow journal and keep tabs on what you're growing and breeding. I'll be starting this with my current seedlings, and documenting as much as possible on future grows and crossing.
Good luck with your Blueberry Hash!