I've been kind of scared to disclose that my puppy is a Shorkie for this same reason, lol. So I'm glad you posted this
For me, while I like the characteristics of Yorkies, I did not want a purebred Yorkie. I wanted a Yorkie mix and for me it was a Shorkie. She's still a puppy so I can't say much about her personality, but looks wise she defintiely looks more Shih Tzu which is what I wanted. She is a bit fearless, though, so that must be her Yorkie side. When it comes to mixed breeds I've read it's best to educate yourself on both breeds as they can most definitely take after each one - they might tend to gravitate towards one breed, but I don't think that's something you'll be able to know until the puppy grows up. There are so many things that contribute to a dog's disposition and I don't think you can say bc it's such and such breed it will be this way and so on. I'm sure you will love it and hopefully be able to train him or her to be the way you wanted it to be, but they do have their own personality.