ST uses PC format disks either 720kb or 360kb
Amigas with Workbench 2.1 or newer natively support the reading of this format of disk too.
It works a treat, I copied a software blitter from a real ST floppy disk with my Amiga onto the hard drive to use with an ST emulator (massive improvement to GEM performance in both real hardware and emulators running on any machine like STEEM on Windows etc)