DiskCopy: https://www.carifred.com/diskcopy/
Freeware (but donations are welcome) and apparently portable.
DiskCopy is a user friendly disk/partition cloning tool. It's ideal for both migration to a faster storage device and data backup.
DiskCopy has really cool features such as:
MBR to GPT and GPT to MBR. You can chose the partition style of the target disk, it does not need to be the same as the source disk's.
Always bootable. The target disk can be made bootable even if the source disk is not booting up.
Partition selection. Copy only the partitions you select.
Single partition cloning. Clone one partition directly to another, and optionally make it bootable.
Full disk/partition management options. Starting with DiskCopy version 1.1.1, DiskCopy includes a Utilities tab with disk/partition management options.
DiskCopy is in Beta stage. Please report any bugs you find to us, using our contact form.
Softpedia page: https://www.softpedia.com/get/System/Ba ... fred.shtml
VirusTotal Score= 0-73
File Size: 1.8Mb
Portability: The downloaded executable runs without installation. I did not test the app any further.
I don't know if DisKCopy leaves traces outside of its folder.