For the C64 mini now exists a workaround for swapping disks creating a cjm file (this is for the pal version):
You have to have a main folder (e.g. called leo) where you put in the cjm, two subfolders with the name: side a/ side b. Put in the respective files for each disk in the corresponding subfolders and name them exactly the same way. If you are prompted to change disks, you just save and load from the second subfolder.