If you transplant now, I wouldn't say there's a big risk of death, unless they aren't watered enough through the Summer. However, they might struggle through and flower weakly. The ones without buds might have trouble fully developing them. Come next Spring though, they'll be right back to the way they are now, if not bigger.

Annabelles are pretty hard to kill, but no matter what they will look terrible this year if you transplant now. Early Spring or Fall is the best time to transplant. If you dont mind deep watering them basically daily and dont care if they bloom this year. You could attempt it and probably be successful. Actually I would pinch any buds/flowers on them to lower their stress and wouldnt feel bad shaving them back some also. The flowers more than likely wont come true anyways after transplant. We all this time of year want to rearrange things in the garden because it is full by this time of the year. We all can finally see what we are working with and want to make our changes to enjoy the rest of the growing season. But if you choose to do it now, I promise it will be a struggle. Like Springwood said next year though they will be fine. Its just all about how much trouble you want to put yourself thru this year. If you can wait till Fall you will save yourself a lot of hassle watering and can enjoy their flowers this year also.