OpenZFS on OS X

Good morning
I just created my first pool.
I see that the ZFS storage presentation choice is EXFAT.

I had to use a small USB key to create the pool when I wanted to use a large partition of a huge disk.
I couldn't say that I wanted to create from a score. I had to say to create from the entire physical support......

My question: Is it planned to be able to use a partition for creating the pool instead of the entire physical media?

ZFS on Windows behaves like every ZFS.
ZFS can use any blockdevice that "smells" like a disk, be it a full disk, a partition, a file or a iSCSI target.

F: is not a blockdevice, more a method for a Windows alike access to an already created ZFS pool or filesystem, so no I would say this will never be possible. So you have to create a pool on the USB stick (physicaldrive x), then assign driveletter f: to it.

btw
If you use removeble USB pools, do not forget to export prior disconnect or ZFS hangs with pending io. To reaccess this pool you need to reboot or reset Windows. As I see it, a ZFS pool is shown as ntfs (up to rc4) and zfs up from rc5