Drag and drop is already available today.  When you drag, it will separate the entry from the repeating series.
We had an account field in the entry dialog (which I just removed because noone was using it) to make space for the addition on a transfer feature.  But you don’t want a repeated transfer from one account.  You want to actually move the entry.
I removed the account field in the interest of keeping things the dialog simple because I don’t think this occurrence will happen too often.  Although it may not happen too often, I can see how you would want to have it happen.