Clone a usb stick in img or to another on Linux by below steps : 

1. Check USB device infomation w/ eg. "/dev/sdb" by "lsblk" commend 

~ $ lsblk

2. Create Image of original USB at filename.img by "dd" commend 

        ~ $ sudo dd if=/dev/sdb of=~/ffp-0.07-230215.img bs=4M status=progress

3. Copy Image to destinated USB by "ddrescue" commend  

~ $ sudo ddrescue /dev/sdb ~/my-usb.img