Decrypt and mount an encrypted sparse bundle disk image using https://github.com/jief666/sparsebundlefs.

mount-encrypted-sparsebundle.sh

# Create mount points for decrypted sparse bundle disk image and full Apple disk image.
sudo mkdir /mnt/bundle /mnt/dmg

# Ensure loopback kernel module is loaded. 
lsmod | grep ^loop || sudo modprobe loop

# Decrypt and FUSE-mount sparse bundle disk image. Trailing options help with debugging.
sudo sparsebundlefs <ENCRYPTED_SPARSE_BUNDLE_DISK_IMAGE> /mnt/bundle -s -f -D

# Note partition 2's "Start" and "Size" values. 
sudo parted /mnt/bundle/sparsebundle.dmg unit B print 
Number  Start       End          Size         File system  Name                  Flags
 1      20480B      209735679B   209715200B   fat32        EFI System Partition  boot, esp
 2      210763776B  4095737855B  3884974080B  fat32        disk image            msftdata

# Using values noted above, associate loop device with decrypted sparse bundle disk image.
sudo losetup -f /mnt/bundle/sparsebundle.dmg --offset 210763776 --sizelimit 3884974080 --show

# Mount loop device as full Apple disk image.
sudo mount /dev/loop0 /mnt/dmg